Reading comprehension I: inference, assumption, corollary and implication: previous-year questions
211 real UPSC Prelims questions (2011–2026) with the official answer and a clear explanation. 62 of them came in the last five papers.
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Read the passage
The number of deaths among the army personnel is 8 in 1000, but among the civilian population it is 20 per 1000.
Which one of the following inferences can be drawn from this statement ?
Answer (d) & explanation
The two groups cannot be compared (d). Step 1: the data show 8 deaths per 1,000 in the army and 20 per 1,000 among civilians. Step 2: think about who is in each group. Soldiers are young, fit and medically screened. Civilians include babies, old people and the sick, who die at higher rates anyway. The groups are heterogeneous (very different), so the lower army death rate does not prove anything about army life. Step 3: test the others. Option (a) is wrong: it treats unlike groups as comparable. Option (b) is too vague. Option (c) is wrong: a Quality of Life index is not shown by death rates alone.
Tip: before comparing two rates, check whether the groups are alike in age and health.
Answer as per the official UPSC answer key.
Read the passage
Given the statement : “Buses are the cause of more accidents than cars, and trucks cause fewer accidents than buses”
Which of the following conclusions can we draw ?
Answer (d) & explanation
No conclusion can be drawn (d). Step 1: the statement only says buses cause more accidents than cars, and trucks fewer than buses. Step 2: test option (a). Accident counts tell us nothing about how many buses and trucks there are on the road, so it fails. Step 3: test (b) and (c). More accidents could be due to more vehicles, longer hours or busier routes, not driver care or skill. Both fail. So none of the conclusions follows.
Tip: raw counts without the base number (how many vehicles, how many kilometres driven) cannot show which group is safer. This idea, comparing rates and not totals, appears often in CSAT logic questions.
Answer as per the official UPSC answer key.
Read the passage
The miseries of the world cannot be cured by physical help only. Until man’s nature changes, his physical needs will always arise, and miseries will always be felt, and no amount of physical help will remove them completely. The only solution of the problem is to make mankind pure. Ignorance is the mother of evil and of all the misery we see. Let men have light, let them be pure and spiritually strong and educated; then alone will misery cease in the world. We may convert every house in the country into a charitable asylum, we may fill the land with hospitals, but human misery will continue until man’s character changes.
According to the passage, which of the following statements is most likely to be true as the reason for man’s miseries ?
Answer (b) & explanation
(b) is correct. Step 1: the passage says 'human misery will continue until man's character changes' and 'Until man's nature changes… miseries will always be felt'. So the root of misery is man's failure to change his character: (b). Step 2: (a) is wrong: poor economic and social conditions are not called the cause; the author says even hospitals and charity everywhere will not end misery. Step 3: (c) is wrong: physical help cannot cure misery, so its absence is not the cause. (d) is wrong: changing social structure is never mentioned. So (a), (c) and (d) fail.
Tip: find the sentence the author repeats in different words; the repeated idea is usually the main reason he gives.
Answer as per the official UPSC answer key.
Read the passage
The miseries of the world cannot be cured by physical help only. Until man’s nature changes, his physical needs will always arise, and miseries will always be felt, and no amount of physical help will remove them completely. The only solution of the problem is to make mankind pure. Ignorance is the mother of evil and of all the misery we see. Let men have light, let them be pure and spiritually strong and educated; then alone will misery cease in the world. We may convert every house in the country into a charitable asylum, we may fill the land with hospitals, but human misery will continue until man’s character changes.
With reference to the passage, the following assumptions have been made :
- 1. The author gives primary importance to physical and material help in eradicating human misery.
- 2. Charitable homes, hospitals, etc. can remove human misery to a great extent.
Which of the assumptions is/are valid ?
Answer (d) & explanation
Neither assumption is valid (d). Step 1: assumption 1 says the author gives primary importance to physical help. The passage says misery 'cannot be cured by physical help only' and that the 'only solution' is to make mankind pure. So 1 is wrong. Step 2: assumption 2 says charitable homes and hospitals can remove misery to a great extent. The author says even if we fill the land with them, 'human misery will continue'. So 2 is wrong. Step 3: so (a), (b) and (c) fail.
Tip: when an author uses 'only' and 'then alone', he is ranking one solution above all others. Assumptions that put any other solution first go against him.
Answer as per the official UPSC answer key.
Read the passage
Seven-year-old Jim came home from the park without his new bicycle. “An old man and a little boy borrowed it,” he explained. “They are going to bring it back at four o’clock.” His parents were upset that he had given his expensive new bicycle, but were secretly proud of his kindness and faith. Came four o’clock, no bicycle. The parents were anxious. But at 4:30, the door bell rang, and there stood a happy man and a boy, with the bicycle and a box of chocolates. Jim suddenly disappeared into his bedroom, and then came running out. “All right,” he said, after examining the bicycle. “You can have your watch back !”
When Jim came home without his bicycle, his parents
Answer (b) & explanation
'Were worried' is correct (b). Step 1: the passage says his parents 'were upset that he had given his expensive new bicycle', and at four o'clock with no bicycle 'the parents were anxious'. Being upset and anxious means worried. Step 2: (a) is wrong: they were 'secretly proud of his kindness and faith', so not angry with him. Step 3: (c) is wrong: they clearly were concerned. (d) is wrong: nothing says they were eager to meet the man and the boy. So (a), (c) and (d) fail.
Tip: collect all the emotion words in the passage (upset, proud, anxious). The answer should fit them together; 'angry' clashes with 'proud'.
Answer as per the official UPSC answer key.
Read the passage
Seven-year-old Jim came home from the park without his new bicycle. “An old man and a little boy borrowed it,” he explained. “They are going to bring it back at four o’clock.” His parents were upset that he had given his expensive new bicycle, but were secretly proud of his kindness and faith. Came four o’clock, no bicycle. The parents were anxious. But at 4:30, the door bell rang, and there stood a happy man and a boy, with the bicycle and a box of chocolates. Jim suddenly disappeared into his bedroom, and then came running out. “All right,” he said, after examining the bicycle. “You can have your watch back !”
Jim returned the watch to the old man and the little boy because
Answer (c) & explanation
(c) is correct. Step 1: Jim said 'All right… You can have your watch back!' only 'after examining the bicycle'. So the watch was security for the bicycle's safe return, and he gave it back once he was satisfied with the bicycle's condition. Step 2: (a) is wrong: the chocolates were a thank-you gift; Jim's reply depends on checking the bicycle. Step 3: (b) is wrong: his father's pride is not linked to the watch. (d) is wrong: being late by 30 minutes is not a reason to return the watch. So (a), (b) and (d) fail.
Tip: the twist at the end of such stories shows the real reason. Read the last lines carefully: here Jim was not just trusting; he was also careful.
Answer as per the official UPSC answer key.
Read the passage
A stout old lady was walking with her basket down the middle of a street in Petrograd to the great confusion of the traffic and no small peril to herself. It was pointed out to her that the pavement was the place for foot-passengers, but she replied, “I’m going to walk where I like. We’ve got liberty now.” It did not occur to the dear lady that if liberty entitled the foot-passenger to walk down the middle of the road it also entitled the taxi-driver to drive on the pavement, and that the end of such liberty would be universal chaos. Everything would be getting in everybody else’s way and nobody would get anywhere. Individual liberty would have become social anarchy.
It was pointed out to the lady that she should walk on the pavement because she was
Answer (a) & explanation
'A pedestrian' is correct (a). Step 1: she was told that 'the pavement was the place for foot-passengers'. A foot-passenger is a pedestrian. So she was asked to use the pavement because she was walking. Step 2: (b) carrying a basket, (c) being stout and (d) being old are descriptions of her, but they are not the reason given. Step 3: the rule applies to every walker, whatever their age, size or luggage. So (b), (c) and (d) fail.
Tip: separate description from reason. Writers add colourful details (stout, old, basket), but the 'because' answer should come from the actual explanation, here the rule about foot-passengers.
Answer as per the official UPSC answer key.
Read the passage
A stout old lady was walking with her basket down the middle of a street in Petrograd to the great confusion of the traffic and no small peril to herself. It was pointed out to her that the pavement was the place for foot-passengers, but she replied, “I’m going to walk where I like. We’ve got liberty now.” It did not occur to the dear lady that if liberty entitled the foot-passenger to walk down the middle of the road it also entitled the taxi-driver to drive on the pavement, and that the end of such liberty would be universal chaos. Everything would be getting in everybody else’s way and nobody would get anywhere. Individual liberty would have become social anarchy.
The lady refused to move from the middle of the street because
Answer (b) & explanation
(b) is correct. Step 1: she replied, 'I'm going to walk where I like. We've got liberty now.' She believed her new freedom entitled her to do whatever she liked: (b). Step 2: (a) is wrong: she was in danger, but the passage does not say she refused because she was not afraid. Step 3: (c) is wrong: she never says she dislikes the pavement. (d) is wrong: it was the traffic that was confused, not her. So (a), (c) and (d) fail.
Tip: when a character's own words explain the action, use them. Note that 'confusion' in the passage belongs to the traffic, a classic word-swap trap.
Answer as per the official UPSC answer key.
Read the passage
A stout old lady was walking with her basket down the middle of a street in Petrograd to the great confusion of the traffic and no small peril to herself. It was pointed out to her that the pavement was the place for foot-passengers, but she replied, “I’m going to walk where I like. We’ve got liberty now.” It did not occur to the dear lady that if liberty entitled the foot-passenger to walk down the middle of the road it also entitled the taxi-driver to drive on the pavement, and that the end of such liberty would be universal chaos. Everything would be getting in everybody else’s way and nobody would get anywhere. Individual liberty would have become social anarchy.
The old lady failed to realise that
Answer (b) & explanation
(b) is correct. Step 1: the author says she did not realise that if liberty let a walker use the middle of the road, it also let a taxi drive on the pavement, ending in 'universal chaos'. So she failed to see that liberty is not unlimited: (b). Step 2: (a) is wrong: she was free; the point is that freedom has limits, not that she lacked it. Step 3: (c) is wrong: her age is irrelevant. (d) is wrong: the author never says roads are for vehicles only. So (a), (c) and (d) fail.
Tip: this is a passage about the limits of rights: one person's freedom ends where it harms others. The answer often has words like 'not unlimited'.
Answer as per the official UPSC answer key.
Read the passage
Chemical pesticides lose their role in sustainable agriculture if the pests evolve resistance. The evolution of pesticide resistance is simply natural selection in action. It is almost certain to occur when vast numbers of a genetically variable population are killed. One or a few individuals may be unusually resistant (perhaps because they possess an enzyme that can detoxify the pesticide). If the pesticide is applied repeatedly, each successive generation of the pest will contain a larger proportion of resistant individuals. Pests typically have a high intrinsic rate of reproduction, and so a few individuals in one generation may give rise to hundreds or thousands in the next, and resistance spreads very rapidly in a population.
This problem was often ignored in the past, even though the first case of DDT (dichlorodiphenyltrichloroethane) resistance was reported as early as 1946. There is exponential increase in the numbers of invertebrates that have evolved resistance and in the number of pesticides against which resistance has evolved. Resistance has been recorded in every family of arthropod pests (including dipterans such as mosquitoes and house flies, as well as beetles, moths, wasps, fleas, lice and mites) as well as in weeds and plant pathogens. Take the Alabama leafworm, a moth pest of cotton, as an example. It has developed resistance in one or more regions of the world to aldrin, DDT, dieldrin, endrin, lindane and toxaphene.
If chemical pesticides brought nothing but problems, — if their use was intrinsically and acutely unsustainable — then they would already have fallen out of widespread use. This has not happened. Instead, their rate of production has increased rapidly. The ratio of cost to benefit for the individual agricultural producer has remained in favour of pesticide use. In the USA, insecticides have been estimated to benefit the agricultural products to the tune of around $5 for every $1 spent.
Moreover, in many poorer countries, the prospect of imminent mass starvation, or of an epidemic disease, are so frightening that the social and health costs of using pesticides have to be ignored. In general the use of pesticides is justified by objective measures such as ‘lives saved’, ‘economic efficiency of food production’ and ‘total food produced’. In these very fundamental senses, their use may be described as sustainable. In practice, sustainability depends on continually developing new pesticides that keep at least one step ahead of the pests — pesticides that are less persistent, biodegradable and more accurately targeted at the pests.
“The evolution of pesticide resistance is natural selection in action.” What does it actually imply ?
Answer (c) & explanation
'Some individuals show resistance' is correct (c). Step 1: the passage explains natural selection here: 'One or a few individuals may be unusually resistant'. When the pesticide kills the rest, these few survive and breed, so each generation has more resistant pests. Step 2: (a) says it is natural for many organisms to be resistant; the passage says only a few are at the start. Step 3: (b) 'universal' overstates even more. Since (c) is right, (d) fails.
Tip: natural selection always starts with a small variation in a few individuals that helps them survive. Options with 'many', 'all' or 'universal' usually overstate such passages.
Answer as per the official UPSC answer key.
Read the passage
We started pitching the highest camp that has ever been made. Everything took five times as long as it would have taken in a place where there was enough air to breathe; but at last we got the tent up, and when we crawled in, it was not too bad. There was only a light wind, and inside it was not too cold for us to take off our gloves. At night most climbers take off their boots; but I prefer to keep them on. Hillary, on the other hand, took his off and laid them next to his sleeping bag.
When they crawled into the tent
Answer (a) & explanation
(a) is correct. Step 1: the passage says 'inside it was not too cold for us to take off our gloves'. So they took their gloves off because it was not very cold. Step 2: (b) and (c) are wrong: both say it was very cold, the opposite of the text. Step 3: (d) is wrong: it says they did not take off their gloves, which reverses the action. So (b), (c) and (d) fail.
Tip: the phrase 'not too cold to do X' means it was warm enough to do X. Options here change one or two small parts (the temperature or the action). Check both parts against the sentence before choosing.
Answer as per the official UPSC answer key.
Read the passage
Chemical pesticides lose their role in sustainable agriculture if the pests evolve resistance. The evolution of pesticide resistance is simply natural selection in action. It is almost certain to occur when vast numbers of a genetically variable population are killed. One or a few individuals may be unusually resistant (perhaps because they possess an enzyme that can detoxify the pesticide). If the pesticide is applied repeatedly, each successive generation of the pest will contain a larger proportion of resistant individuals. Pests typically have a high intrinsic rate of reproduction, and so a few individuals in one generation may give rise to hundreds or thousands in the next, and resistance spreads very rapidly in a population.
This problem was often ignored in the past, even though the first case of DDT (dichlorodiphenyltrichloroethane) resistance was reported as early as 1946. There is exponential increase in the numbers of invertebrates that have evolved resistance and in the number of pesticides against which resistance has evolved. Resistance has been recorded in every family of arthropod pests (including dipterans such as mosquitoes and house flies, as well as beetles, moths, wasps, fleas, lice and mites) as well as in weeds and plant pathogens. Take the Alabama leafworm, a moth pest of cotton, as an example. It has developed resistance in one or more regions of the world to aldrin, DDT, dieldrin, endrin, lindane and toxaphene.
If chemical pesticides brought nothing but problems, — if their use was intrinsically and acutely unsustainable — then they would already have fallen out of widespread use. This has not happened. Instead, their rate of production has increased rapidly. The ratio of cost to benefit for the individual agricultural producer has remained in favour of pesticide use. In the USA, insecticides have been estimated to benefit the agricultural products to the tune of around $5 for every $1 spent.
Moreover, in many poorer countries, the prospect of imminent mass starvation, or of an epidemic disease, are so frightening that the social and health costs of using pesticides have to be ignored. In general the use of pesticides is justified by objective measures such as ‘lives saved’, ‘economic efficiency of food production’ and ‘total food produced’. In these very fundamental senses, their use may be described as sustainable. In practice, sustainability depends on continually developing new pesticides that keep at least one step ahead of the pests — pesticides that are less persistent, biodegradable and more accurately targeted at the pests.
With reference to the passage, consider the following statements :
- 1. Use of chemical pesticides has become imperative in all the poor countries of the world.
- 2. Chemical pesticides should not have any role in sustainable agriculture.
- 3. One pest can develop resistance to many pesticides.
Which of the statements given above is/are correct ?
Answer (b) & explanation
Only statement 3 is correct (b). Step 1: the Alabama leafworm has become resistant to six pesticides (aldrin, DDT, dieldrin, endrin, lindane, toxaphene). So one pest can resist many pesticides: 3 is right. Step 2: statement 1 says pesticides are imperative in all poor countries. The passage only says 'many poorer countries' face fears of starvation or epidemics. So 1 overstates. Step 3: statement 2 says pesticides should have no role in sustainable agriculture. The passage calls their use sustainable 'in these very fundamental senses'. So 2 is wrong, and (a), (c) and (d) fail.
Tip: compare quantity words carefully: 'many' in the passage never supports 'all' in an option.
Answer as per the official UPSC answer key.
Read the passage
Chemical pesticides lose their role in sustainable agriculture if the pests evolve resistance. The evolution of pesticide resistance is simply natural selection in action. It is almost certain to occur when vast numbers of a genetically variable population are killed. One or a few individuals may be unusually resistant (perhaps because they possess an enzyme that can detoxify the pesticide). If the pesticide is applied repeatedly, each successive generation of the pest will contain a larger proportion of resistant individuals. Pests typically have a high intrinsic rate of reproduction, and so a few individuals in one generation may give rise to hundreds or thousands in the next, and resistance spreads very rapidly in a population.
This problem was often ignored in the past, even though the first case of DDT (dichlorodiphenyltrichloroethane) resistance was reported as early as 1946. There is exponential increase in the numbers of invertebrates that have evolved resistance and in the number of pesticides against which resistance has evolved. Resistance has been recorded in every family of arthropod pests (including dipterans such as mosquitoes and house flies, as well as beetles, moths, wasps, fleas, lice and mites) as well as in weeds and plant pathogens. Take the Alabama leafworm, a moth pest of cotton, as an example. It has developed resistance in one or more regions of the world to aldrin, DDT, dieldrin, endrin, lindane and toxaphene.
If chemical pesticides brought nothing but problems, — if their use was intrinsically and acutely unsustainable — then they would already have fallen out of widespread use. This has not happened. Instead, their rate of production has increased rapidly. The ratio of cost to benefit for the individual agricultural producer has remained in favour of pesticide use. In the USA, insecticides have been estimated to benefit the agricultural products to the tune of around $5 for every $1 spent.
Moreover, in many poorer countries, the prospect of imminent mass starvation, or of an epidemic disease, are so frightening that the social and health costs of using pesticides have to be ignored. In general the use of pesticides is justified by objective measures such as ‘lives saved’, ‘economic efficiency of food production’ and ‘total food produced’. In these very fundamental senses, their use may be described as sustainable. In practice, sustainability depends on continually developing new pesticides that keep at least one step ahead of the pests — pesticides that are less persistent, biodegradable and more accurately targeted at the pests.
Though the problems associated with the use of chemical pesticides is known for a long time, their widespread use has not waned. Why ?
Answer (d) & explanation
None of these is correct (d). Step 1: the passage gives the real reason pesticide use has not fallen: the cost-to-benefit ratio 'has remained in favour of pesticide use' (about $5 of benefit for $1 spent in the USA). None of the options says this. Step 2: (a) the passage never says alternatives do not exist at all. (b) is false: it speaks of 'continually developing new pesticides'. Step 3: (c) is wrong because the passage only hopes for future pesticides that are 'biodegradable'; it does not say present ones are. So (a), (b) and (c) fail.
Tip: when the true reason is missing from the options, 'none of the above' is a real choice. Check each option against the text before ruling it out.
Answer as per the official UPSC answer key.
Read the passage
Chemical pesticides lose their role in sustainable agriculture if the pests evolve resistance. The evolution of pesticide resistance is simply natural selection in action. It is almost certain to occur when vast numbers of a genetically variable population are killed. One or a few individuals may be unusually resistant (perhaps because they possess an enzyme that can detoxify the pesticide). If the pesticide is applied repeatedly, each successive generation of the pest will contain a larger proportion of resistant individuals. Pests typically have a high intrinsic rate of reproduction, and so a few individuals in one generation may give rise to hundreds or thousands in the next, and resistance spreads very rapidly in a population.
This problem was often ignored in the past, even though the first case of DDT (dichlorodiphenyltrichloroethane) resistance was reported as early as 1946. There is exponential increase in the numbers of invertebrates that have evolved resistance and in the number of pesticides against which resistance has evolved. Resistance has been recorded in every family of arthropod pests (including dipterans such as mosquitoes and house flies, as well as beetles, moths, wasps, fleas, lice and mites) as well as in weeds and plant pathogens. Take the Alabama leafworm, a moth pest of cotton, as an example. It has developed resistance in one or more regions of the world to aldrin, DDT, dieldrin, endrin, lindane and toxaphene.
If chemical pesticides brought nothing but problems, — if their use was intrinsically and acutely unsustainable — then they would already have fallen out of widespread use. This has not happened. Instead, their rate of production has increased rapidly. The ratio of cost to benefit for the individual agricultural producer has remained in favour of pesticide use. In the USA, insecticides have been estimated to benefit the agricultural products to the tune of around $5 for every $1 spent.
Moreover, in many poorer countries, the prospect of imminent mass starvation, or of an epidemic disease, are so frightening that the social and health costs of using pesticides have to be ignored. In general the use of pesticides is justified by objective measures such as ‘lives saved’, ‘economic efficiency of food production’ and ‘total food produced’. In these very fundamental senses, their use may be described as sustainable. In practice, sustainability depends on continually developing new pesticides that keep at least one step ahead of the pests — pesticides that are less persistent, biodegradable and more accurately targeted at the pests.
How do pesticides act as agents for the selection of resistant individuals in any pest population ?
- 1. It is possible that in a pest population the individuals will behave differently due to their genetic makeup.
- 2. Pests do possess the ability to detoxify the pesticides.
- 3. Evolution of pesticide resistance is equally distributed in pest population.
Which of the statements given above is/are correct ?
Answer (b) & explanation
Statements 1 and 2 are correct (b). Step 1: the passage speaks of a 'genetically variable population', so individuals respond differently because of their genes: 1 is right. Step 2: it says a few may be resistant 'perhaps because they possess an enzyme that can detoxify the pesticide': 2 is right. Step 3: statement 3 says resistance is equally distributed. The passage says it begins in 'one or a few individuals' and spreads over generations, so it is unequal at first. So 3 is wrong, and (a), (c) and (d) fail.
Tip: selection works only because individuals differ. Any statement saying everyone is the same ('equally distributed') goes against the whole idea of selection.
Answer as per the official UPSC answer key.
Read the passage
Chemical pesticides lose their role in sustainable agriculture if the pests evolve resistance. The evolution of pesticide resistance is simply natural selection in action. It is almost certain to occur when vast numbers of a genetically variable population are killed. One or a few individuals may be unusually resistant (perhaps because they possess an enzyme that can detoxify the pesticide). If the pesticide is applied repeatedly, each successive generation of the pest will contain a larger proportion of resistant individuals. Pests typically have a high intrinsic rate of reproduction, and so a few individuals in one generation may give rise to hundreds or thousands in the next, and resistance spreads very rapidly in a population.
This problem was often ignored in the past, even though the first case of DDT (dichlorodiphenyltrichloroethane) resistance was reported as early as 1946. There is exponential increase in the numbers of invertebrates that have evolved resistance and in the number of pesticides against which resistance has evolved. Resistance has been recorded in every family of arthropod pests (including dipterans such as mosquitoes and house flies, as well as beetles, moths, wasps, fleas, lice and mites) as well as in weeds and plant pathogens. Take the Alabama leafworm, a moth pest of cotton, as an example. It has developed resistance in one or more regions of the world to aldrin, DDT, dieldrin, endrin, lindane and toxaphene.
If chemical pesticides brought nothing but problems, — if their use was intrinsically and acutely unsustainable — then they would already have fallen out of widespread use. This has not happened. Instead, their rate of production has increased rapidly. The ratio of cost to benefit for the individual agricultural producer has remained in favour of pesticide use. In the USA, insecticides have been estimated to benefit the agricultural products to the tune of around $5 for every $1 spent.
Moreover, in many poorer countries, the prospect of imminent mass starvation, or of an epidemic disease, are so frightening that the social and health costs of using pesticides have to be ignored. In general the use of pesticides is justified by objective measures such as ‘lives saved’, ‘economic efficiency of food production’ and ‘total food produced’. In these very fundamental senses, their use may be described as sustainable. In practice, sustainability depends on continually developing new pesticides that keep at least one step ahead of the pests — pesticides that are less persistent, biodegradable and more accurately targeted at the pests.
Why is the use of chemical pesticides generally justified by giving the examples of poor and developing countries ?
- 1. Developed countries can afford to do away with use of pesticides by adapting to organic farming, but it is imperative for poor and developing countries to use chemical pesticides.
- 2. In poor and developing countries, the pesticide addresses the problem of epidemic diseases of crops and eases the food problem.
- 3. The social and health costs of pesticide use are generally ignored in poor and developing countries.
Which of the statements given above is/are correct ?
Answer (c) & explanation
Only statement 2 is correct (c). Step 1: the passage says in poorer countries 'the prospect of imminent mass starvation, or of an epidemic disease' is so frightening that pesticides are used. That is the justification: they ease food problems and disease: 2 is right. Step 2: statement 1 talks about organic farming in developed countries, which the passage never mentions. Step 3: statement 3 is a result of that fear (the costs 'have to be ignored'), not the reason for using pesticides. The question asks why use is justified, so 3 fails. Hence (a), (b) and (d) are wrong.
Tip: separate the reason from the consequence. A true fact from the passage can still be the wrong answer to a 'why' question.
Answer as per the official UPSC answer key.
Read the passage
Chemical pesticides lose their role in sustainable agriculture if the pests evolve resistance. The evolution of pesticide resistance is simply natural selection in action. It is almost certain to occur when vast numbers of a genetically variable population are killed. One or a few individuals may be unusually resistant (perhaps because they possess an enzyme that can detoxify the pesticide). If the pesticide is applied repeatedly, each successive generation of the pest will contain a larger proportion of resistant individuals. Pests typically have a high intrinsic rate of reproduction, and so a few individuals in one generation may give rise to hundreds or thousands in the next, and resistance spreads very rapidly in a population.
This problem was often ignored in the past, even though the first case of DDT (dichlorodiphenyltrichloroethane) resistance was reported as early as 1946. There is exponential increase in the numbers of invertebrates that have evolved resistance and in the number of pesticides against which resistance has evolved. Resistance has been recorded in every family of arthropod pests (including dipterans such as mosquitoes and house flies, as well as beetles, moths, wasps, fleas, lice and mites) as well as in weeds and plant pathogens. Take the Alabama leafworm, a moth pest of cotton, as an example. It has developed resistance in one or more regions of the world to aldrin, DDT, dieldrin, endrin, lindane and toxaphene.
If chemical pesticides brought nothing but problems, — if their use was intrinsically and acutely unsustainable — then they would already have fallen out of widespread use. This has not happened. Instead, their rate of production has increased rapidly. The ratio of cost to benefit for the individual agricultural producer has remained in favour of pesticide use. In the USA, insecticides have been estimated to benefit the agricultural products to the tune of around $5 for every $1 spent.
Moreover, in many poorer countries, the prospect of imminent mass starvation, or of an epidemic disease, are so frightening that the social and health costs of using pesticides have to be ignored. In general the use of pesticides is justified by objective measures such as ‘lives saved’, ‘economic efficiency of food production’ and ‘total food produced’. In these very fundamental senses, their use may be described as sustainable. In practice, sustainability depends on continually developing new pesticides that keep at least one step ahead of the pests — pesticides that are less persistent, biodegradable and more accurately targeted at the pests.
What does the passage imply ?
Answer (d) & explanation
Both (a) and (b) is the official key (d). Step 1: the passage shows heavy chemical use leads to resistance in every pest family and to social and health costs. That implies too much chemical use is not good for the ecosystem (b). Step 2: from the same problems, the key reads support for alternatives (a). Step 3: (c) is clearly wrong: the passage says sustainability depends on new, better pesticides that are less persistent and more targeted, so there is scope for improvement. Note: (a) is DOUBTFUL, because the passage never mentions alternatives; it pins its hope on improved pesticides. (b) alone is arguable, but UPSC's key is (d).
Tip: 'implies' questions allow reasonable inference, but stay close to the text.
Answer as per the official UPSC answer key.
Read the passage
For fourteen and a half months I lived in my little cell or room in the Dehradun jail, and I began to feel as if I was almost a part of it. I was familiar with every bit of it, I knew every mark and dent on the whitewashed walls and on the uneven floor and the ceiling with its moth-eaten rafters. In the little yard outside I greeted little tufts of grass and odd bits of stone as old friends. I was not alone in my cell, for several colonies of wasp and hornets lived there, and many lizards found a home behind the rafters, emerging in the evenings in search of prey.
Which of the following explains best the sentence in the passage “I was almost a part of it” ?
Answer (b) & explanation
(b) is correct. Step 1: the very next sentence explains the phrase: 'I was familiar with every bit of it, I knew every mark and dent on the… walls'. Feeling part of the cell means knowing it in every detail. Step 2: (a) 'not alone' refers to the wasps and lizards, a different point. (c) greeting grass as friends is about the yard outside, not the cell. Step 3: (d) 'felt quite at home' is a close distractor, but the passage never says he felt comfortable; it stresses familiarity. So (a), (c) and (d) fail.
Tip: when asked to explain a phrase, look at the sentence right after it. Authors often explain their own words there.
Answer as per the official UPSC answer key.
Read the passage
For fourteen and a half months I lived in my little cell or room in the Dehradun jail, and I began to feel as if I was almost a part of it. I was familiar with every bit of it, I knew every mark and dent on the whitewashed walls and on the uneven floor and the ceiling with its moth-eaten rafters. In the little yard outside I greeted little tufts of grass and odd bits of stone as old friends. I was not alone in my cell, for several colonies of wasp and hornets lived there, and many lizards found a home behind the rafters, emerging in the evenings in search of prey.
The passage attempts to describe
Answer (c) & explanation
(c) is correct. Step 1: the prisoner knows every dent in the walls, greets 'little tufts of grass and odd bits of stone as old friends', and notices the wasps, hornets and lizards that share his cell. These details show a man making a conscious effort to cope with loneliness. Step 2: (a) is wrong: he describes one cell, not the country's jails in general. Step 3: (b) is true on the surface, but noticing details is the means, not the purpose. (d) overstates: he does not say he lived happily with the creatures. So (a), (b) and (d) fail.
Tip: ask why the author gives these details. The purpose behind them is usually the main idea.
Answer as per the official UPSC answer key.
Read the passage
For fourteen and a half months I lived in my little cell or room in the Dehradun jail, and I began to feel as if I was almost a part of it. I was familiar with every bit of it, I knew every mark and dent on the whitewashed walls and on the uneven floor and the ceiling with its moth-eaten rafters. In the little yard outside I greeted little tufts of grass and odd bits of stone as old friends. I was not alone in my cell, for several colonies of wasp and hornets lived there, and many lizards found a home behind the rafters, emerging in the evenings in search of prey.
The author of the passage seems to suggest that
Answer (a) & explanation
(a) is correct. Step 1: over fourteen and a half months, the prisoner came to feel 'almost a part of' a bare cell with dents, moth-eaten rafters and insects. This shows a person can adjust to unpleasant surroundings. Step 2: (b) and (d) are wrong: he does not judge whether Indian prisons are good or need improvement. Step 3: (c) is wrong: he never says prison life is easy; the effort to find company in grass and stones shows it was hard. So (b), (c) and (d) fail.
Tip: 'the author seems to suggest' asks for the general lesson from the story. Choose the broad idea and reject options about topics (prison policy) the author never discusses.
Answer as per the official UPSC answer key.
Read the passage
We started pitching the highest camp that has ever been made. Everything took five times as long as it would have taken in a place where there was enough air to breathe; but at last we got the tent up, and when we crawled in, it was not too bad. There was only a light wind, and inside it was not too cold for us to take off our gloves. At night most climbers take off their boots; but I prefer to keep them on. Hillary, on the other hand, took his off and laid them next to his sleeping bag.
What does the expression “pitching the highest camp” imply ?
Answer (c) & explanation
(c) is correct. Step 1: the author says they were pitching 'the highest camp that has ever been made'. So nobody had ever camped that high before. Step 2: (a) is wrong: they were still pitching a camp, so they had not yet reached the summit. Step 3: (b) is wrong: the passage does not say earlier climbers reached that height without camping; it implies no one had camped there. (d) is wrong: 'highest' refers to height, not to a big camp for many climbers. So (a), (b) and (d) fail.
Tip: read the key word carefully: 'highest' is about altitude. Do not mix up 'high' with 'large'. 'Ever' makes it a record.
Answer as per the official UPSC answer key.