UPSC Prelims PYQs with explanations
Real questions from official papers, mapped to syllabus topics. Attempt each one; the answer and the reason appear instantly.
With reference to medieval India, which one of the following is the correct sequence in ascending order in terms of size?
Answer (a) & explanation
Pargana, sarkar, suba is the ascending order (a). In Akbar's administration, the empire was divided into subas (provinces), each suba into sarkars (districts), and each sarkar into parganas, which were groups of villages. So from smallest to largest the order is pargana, sarkar, suba. Options (b), (c) and (d) mix up this order. The suba was run by the subedar (governor) with a diwan for revenue; the sarkar by the faujdar; and the pargana by the shiqdar and the amil.
Notice that Akbar had 12 subas at first, which rose to 15 by the end of his reign. The revenue system was the zabt or dahsala system of Raja Todar Mal.
Answer as per the official UPSC answer key.
With reference to the Union Government, consider the following statements :
- 1. N. Gopalaswamy Iyengar Committee suggested that a minister and a secretary be designated solely for pursuing the subject of administrative reform and promoting it.
- 2. In 1970, the Department of Personnel was constituted on the recommendation of the Administrative Reforms Commission, 1966, and this was placed under the Prime Minister's charge.
Which of the statements given above is/are correct?
Answer (b) & explanation
Only statement 2 is correct (b). Statement 1 is wrong per the key: the N. Gopalaswamy Ayyangar report (1949) dealt with reorganising the machinery of government, mainly the grouping of ministries, and did not propose a minister and secretary solely for administrative reform. Statement 2 is right: the First Administrative Reforms Commission (1966), first chaired by Morarji Desai and later by K. Hanumanthaiya, led to the Department of Personnel in 1970, placed under the Prime Minister.
Notice that the Department of Personnel is now part of the Ministry of Personnel, Public Grievances and Pensions, still under the PM. The Second ARC (2005), chaired first by Veerappa Moily, gave 15 reports.
Answer as per the official UPSC answer key.
From January 1, 2021, the price of petrol (in Rupees per litre) on mth day of the year is 80 + 0·1m, where m = 1, 2, 3, ..., 100 and thereafter remains constant. On the other hand, the price of diesel (in Rupees per litre) on nth day of 2021 is 69 + 0·15n for any n. On which date in the year 2021 are the prices of these two fuels equal ?
Answer (b) & explanation
The prices are equal on 20th May (b). Step 1: in the first 100 days, petrol = 80 + 0·1m and diesel = 69 + 0·15n. Setting them equal gives 0·05n = 11, so n = 220. That is outside the first 100 days, so there is no match there. Step 2: after day 100, petrol stays at 80 + 10 = ₹ 90. Diesel = 90 when 69 + 0·15n = 90, so n = 140. Step 3: day 140 of 2021: January to April = 31 + 28 + 31 + 30 = 120 days. Day 140 is the 20th of May. Options (a), (c) and (d) are off by a day.
Tip: always check the range where a formula applies. 2021 is not a leap year, so February has 28 days.
the petrol formula stops at day 100. Using it beyond that gives a wrong day.
Answer as per the official UPSC answer key.
Consider two Statements and a Question :
Statement-1 : Each of A and D is heavier than each of B, E and F, but none of them is the heaviest.
Statement-2 : A is heavier than D, but is lighter than C.
Question : Who is the heaviest among A, B, C, D and E ?
Which one of the following is correct in respect of the Statements and the Question ?
Answer (c) & explanation
1. Statement-1 alone: A and D beat B, E and F, but we are not told who beats A and D. C is never mentioned, so we cannot name the heaviest.
2. Statement-2 alone: C > A > D. We know nothing about B and E, so again we cannot say.
3. Together: C > A > D, and A, D are heavier than B and E. So C is the heaviest, and both statements are needed (c).
4. A different reading of Statement-1 makes the data unclear, which is why (d) is also accepted.
The words 'none of them' can be read two ways, so UPSC's final key accepts both (c) and (d).
Answer as per the official UPSC answer key.
Read the passage
Medieval merchants risked the hazards of the Silk Road to reach the markets of China; Portuguese caravels in the 15 century sailed beyond the bounds of the known world, searching less for knowledge than for gold and spices. Historically, the driver for opening frontiers has always been the search for resources. Science and curiosity are weaker drivers. The only way to open up space, whether the space of solar system or interstellar space is to create an economic engine and that engine is resource extraction.
Which one of the following statements best sums up the passage given above ?
Answer (c) & explanation
The passage is best summed up as: humans explore new frontiers mainly for economic reasons (c). Step 1: it gives examples: medieval merchants on the Silk Road and Portuguese ships seeking gold and spices. Step 2: it says "the driver for opening frontiers has always been the search for resources", and space too needs an economic engine. That is (c). Step 3: option (a) widens it to any human endeavour, but the passage talks only of frontiers. Option (b) predicts space will govern the economy, which is not said. Option (d), risk-taking, is not the main point.
Tip: watch the scope. An option that stretches "frontiers" to "every human activity" goes beyond the passage.
Answer as per the official UPSC answer key.
Consider the following animals :
- 1. Hedgehog
- 2. Marmot
- 3. Pangolin
To reduce the chance of being captured by predators, which of the above organisms rolls up/roll up and protects/protect its/their vulnerable parts?
Answer (d) & explanation
The hedgehog and pangolin roll up (d). Item 1 is right: a hedgehog curls into a tight ball of spines when threatened, hiding its soft belly and face. Item 3 is right: a pangolin rolls into a ball of hard, overlapping scales made of keratin, which even lions find hard to break. Item 2 is wrong: a marmot is a large ground squirrel of mountains; it gives a loud whistle to warn others and runs into its burrow.
Notice that the pangolin is the world's most trafficked mammal, hunted for its scales and meat. India has the Indian pangolin and the Chinese pangolin, both in Schedule I. The Himalayan marmot lives in Ladakh and Sikkim.
Answer as per the official UPSC answer key.
Among the following, which one is the least water-efficient crop?
Answer (a) & explanation
Sugarcane is the least water-efficient crop (a). Sugarcane stays in the field for 10–18 months and needs about 1,500–2,500 mm of water. In India, roughly 2,000 litres or more go into one kilogram of sugar. Sunflower (b) needs only moderate water. Pearl millet (c), or bajra, is a hardy dryland crop that grows with little rain. Red gram (d), or arhar, is a deep-rooted pulse that also tolerates drought.
Notice that much of India's sugarcane is grown in water-scarce Maharashtra and Karnataka, which worsens groundwater stress. Drip irrigation can save a lot of water in sugarcane. 2023 was the International Year of Millets, which promoted water-thrifty crops such as bajra.
Answer as per the official UPSC answer key.
Under the Indian Constitution, concentration of wealth violates
Answer (b) & explanation
Concentration of wealth violates the Directive Principles (b). Article 39(c) directs the State to ensure that the operation of the economic system does not result in the concentration of wealth and means of production to the common detriment. It is a Directive Principle of State Policy. Option (a) is wrong: the Right to Equality (Articles 14–18) deals with legal equality and discrimination. Option (c) is wrong: the Right to Freedom (Articles 19–22) covers speech, movement and life. Option (d) is wrong: the "concept of welfare" is a broad idea, not a constitutional provision.
Notice that the 25th Amendment (1971) added Article 31C to protect laws giving effect to Article 39(b) and (c). Directive Principles are not enforceable in court (Article 37).
Answer as per the official UPSC answer key.
A bank employee drives 10 km towards South from her house and turns to her left and drives another 20 km. She again turns left and drives 40 km, then she turns to her right and drives for another 5 km. She again turns to her right and drives another 30 km to reach her bank where she works. What is the shortest distance between her bank and her house ?
Answer (b) & explanation
The shortest distance is 25 km (b). Step 1: trace the path. South 10 km. Facing South, left is East: 20 km. Facing East, left is North: 40 km. Facing North, right is East: 5 km. Facing East, right is South: 30 km. Step 2: north-south: −10 + 40 − 30 = 0. She ends on the same level as her house. East: 20 + 5 = 25 km. Step 3: so the bank is 25 km due East of the house. Options (a), (c) and (d) fail.
Tip: add up all north-south moves and all east-west moves separately. If one adds to zero, the answer is simply the other total.
Answer as per the official UPSC answer key.
What is the value of 'X' in the sequence 2, 7, 22, 67, 202, X, 1822 ?
Answer (c) & explanation
X is 607 (c). Step 1: look at how each term is made from the one before. 2 × 3 + 1 = 7; 7 × 3 + 1 = 22; 22 × 3 + 1 = 67; 67 × 3 + 1 = 202. The rule is × 3, then + 1. Step 2: so X = 202 × 3 + 1 = 607. Step 3: check with the next term: 607 × 3 + 1 = 1822. It matches. Options (a) 603, (b) 605 and (d) 608 fail this check.
Tip: when terms grow about three times each step, try "× 3 ± a small number". Always confirm using the term after the blank.
Answer as per the official UPSC answer key.
With reference to casual workers employed in India, consider the following statements :
- 1. All casual workers are entitled for Employees Provident Fund coverage.
- 2. All casual workers are entitled for regular working hours and overtime payment.
- 3. The government can by a notification specify that an establishment or industry shall pay wages only through its bank account.
Which of the above statements are correct?
Answer (b) & explanation
Statements 2 and 3 are correct (b). Statement 1 is wrong: the EPF scheme covers only establishments with 20 or more workers, and members earning within the wage ceiling (₹15,000 a month), so not every casual worker is covered. Statement 2 is right: labour laws on working hours and overtime apply to all workers, including casual ones. Statement 3 is right: the Code on Wages, 2019 lets the government notify that an establishment or industry must pay wages only by cheque or into the worker's bank account.
Notice the four labour codes: Wages (2019), Industrial Relations, Social Security, and Occupational Safety, Health and Working Conditions (2020). They merged 29 central labour laws and came into force in November 2025. The e-Shram portal registers unorganised workers.
Answer as per the official UPSC answer key.
From the decline of Guptas until the rise of Harshavardhana in the early seventh century, which of the following kingdoms were holding power in Northern India?
- 1. The Guptas of Magadha
- 2. The Paramaras of Malwa
- 3. The Pushyabhutis of Thanesar
- 4. The Maukharis of Kanauj
- 5. The Yadavas of Devagiri
- 6. The Maitrakas of Valabhi
Select the correct answer using the code given below.
Answer (b) & explanation
The Later Guptas, Pushyabhutis, Maukharis and Maitrakas held power (b). In the 6th century, after the imperial Guptas declined, north India split among regional powers. Item 1 is right: the Later Guptas ruled Magadha. Item 3 is right: the Pushyabhutis of Thanesar were Harsha's family. Item 4 is right: the Maukharis ruled from Kanauj. Item 6 is right: the Maitrakas ruled Valabhi in Gujarat, a famous centre of learning. Item 2 is wrong: the Paramaras of Malwa rose in the 10th century. Item 5 is wrong: the Yadavas of Devagiri rose in the 12th century.
Notice that Harsha's sister Rajyashri married the Maukhari king Grahavarman, which is how Harsha came to rule Kanauj. Notice Shashanka of Gauda, Harsha's enemy.
Answer as per the official UPSC answer key.
In a pressure cooker, the temperature at which the food is cooked depends mainly upon which of the following?
- 1. Area of the hole in the lid
- 2. Temperature of the flame
- 3. Weight of the lid
Select the correct answer using the code given below.
Answer (c) & explanation
The hole area and lid weight set the temperature (c). Water boils at a higher temperature when the pressure is higher. In a pressure cooker, the pressure inside is set by the weight of the whistle on the vent divided by the area of the hole. Item 3 is right: a heavier weight holds more pressure. Item 1 is right: a smaller hole means the same weight holds more pressure. Item 2 is wrong: a hotter flame only makes the cooker reach that pressure sooner and release more steam; it does not raise the cooking temperature.
Notice the reverse case: at high altitude, low air pressure makes water boil below 100 °C, so food cooks slowly. That is why pressure cookers are vital in the mountains. Typical cookers reach about 120 °C.
Answer as per the official UPSC answer key.
A legislation which confers on the executive or administrative authority an unguided and uncontrolled discretionary power in the matter of application of law violates which one of the following Articles of the Constitution of India?
Answer (a) & explanation
Unguided discretion violates Article 14 (a). Article 14 guarantees equality before law and equal protection of the laws. Since E.P. Royappa (1974), the Supreme Court has treated arbitrariness as the opposite of equality. A law that hands officials unguided and uncontrolled discretion lets them treat equals unequally, so it fails Article 14. Article 28 (b) deals with religious instruction in schools. Article 32 (c) is the right to move the Supreme Court for remedies. Article 44 (d) is the Directive on a Uniform Civil Code.
Notice Maneka Gandhi (1978), which linked Articles 14, 19 and 21 (the golden triangle). The Shayara Bano case (2017) used manifest arbitrariness to strike down triple talaq.
Answer as per the official UPSC answer key.
A person X from a place A and another person Y from a place B set out at the same time to walk towards each other. The places are separated by a distance of 15 km. X walks with a uniform speed of 1·5 km/hr and Y walks with a uniform speed of 1 km/hr in the first hour, with a uniform speed of 1·25 km/hr in the second hour and with a uniform speed of 1·5 km/hr in the third hour and so on. Which of the following is/are correct ?
- 1. They take 5 hours to meet.
- 2. They meet midway between A and B.
Select the correct answer using the code given below :
Answer (c) & explanation
Both statements are correct (c). Step 1: X walks at a steady 1.5 km/hr. In 5 hours X covers 1.5 × 5 = 7.5 km. Step 2: Y's speed rises by 0.25 each hour: 1, 1.25, 1.5, 1.75, 2. In 5 hours Y covers 1 + 1.25 + 1.5 + 1.75 + 2 = 7.5 km. Step 3: together they cover 7.5 + 7.5 = 15 km, the full distance. So they meet after 5 hours (statement 1). Each has walked 7.5 km, which is exactly midway (statement 2). So options (a), (b) and (d) fail.
Tip: Y's speeds average 1.5 km/hr over those 5 hours, the same as X. Equal average speeds for equal time mean equal distance.
Answer as per the official UPSC answer key.
Read the passage
Can a democracy avoid being a welfare state for long ? Why cannot mass welfare be left entirely to the markets ? There is a built-in tension between markets and democracy. Markets do not work on a one-person-one-vote principle as democracies do. What one gets out of the market place depends on one’s endowments, skills, purchasing power and the forces of demand and supply. Markets reward individual initiative and skill, and may also lift many from the bottom rungs of society, but some people never get the opportunity to develop skills that markets demand; they are simply too poor and too handicapped; or skill formation takes too long. By creating jobs, markets may be able to help even unskilled people, but capitalism has always witnessed bursts of unemployment.
With reference to the above passage, the following assumptions have been made :
- 1. Modern democracies rely on the market forces to enable them to be welfare states.
- 2. Markets ensure sufficient economic growth necessary for democracies to be effective.
- 3. Government programmes are needed for those left behind in economic growth.
Which of the above assumptions is/are valid ?
Answer (b) & explanation
Only assumption 3 is valid (b). Step 1: the passage asks why welfare cannot be "left entirely to the markets". It says some people never get to build the skills markets reward, and capitalism sees bursts of unemployment. So government programmes are needed for those left behind (3). Step 2: assumption 1 says democracies rely on markets to be welfare states. The passage says the opposite. Step 3: assumption 2 says markets ensure enough growth for democracy. The passage only says markets may lift some people. So options (a), (c) and (d) fail.
Tip: the tension between markets and democracy is a key idea. Markets work on "one rupee, one vote"; democracy works on "one person, one vote".
Answer as per the official UPSC answer key.
With reference to India, consider the following statements :
- 1. Retail investors through demat account can invest in 'Treasury Bills' and 'Government of India Debt Bonds' in primary market.
- 2. The 'Negotiated Dealing System-Order Matching' is a government securities trading platform of the Reserve Bank of India.
- 3. The 'Central Depository Services Ltd.' is jointly promoted by the Reserve Bank of India and the Bombay Stock Exchange.
Which of the statements given above is/are correct?
Answer (b) & explanation
Statements 1 and 2 are correct (b). Statement 1 is right: retail investors can bid for Treasury Bills and government bonds in primary auctions through their demat accounts and stock exchanges, as non-competitive bidders. Statement 2 is right: NDS-OM (Negotiated Dealing System–Order Matching) is the RBI's electronic, screen-based platform for trading government securities. Statement 3 is wrong: CDSL was promoted by the BSE together with banks such as SBI, Bank of Baroda and HDFC Bank, not by the RBI.
Notice the RBI Retail Direct scheme (2021), which lets individuals open a gilt account directly with the RBI. India's other depository is NSDL, promoted by IDBI, UTI and NSE.
Answer as per the official UPSC answer key.
In the context of Colonial India, Shah Nawaz Khan, Prem Kumar Sehgal and Gurbaksh Singh Dhillon are remembered as
Answer (d) & explanation
They were officers of the Indian National Army (d). Shah Nawaz Khan, Prem Kumar Sehgal and Gurbaksh Singh Dhillon, a Muslim, a Hindu and a Sikh, were INA officers tried together for treason at the Red Fort in November 1945. Bhulabhai Desai led the defence, with Nehru and Tej Bahadur Sapru on the team. Protests across the country forced the government to remit their sentences. They were not linked with the Swadeshi movement (a), the Interim Government (b) or the Drafting Committee (c).
Notice the slogan "Lal Qila se aai awaaz, Sehgal, Dhillon, Shah Nawaz". The INA trials, along with the Royal Indian Navy mutiny (1946), showed the British they could no longer rely on Indian forces.
Answer as per the official UPSC answer key.
'Right to Privacy' is protected under which Article of the Constitution of India?
Answer (c) & explanation
Privacy is protected under Article 21 (c). A nine-judge bench in Justice K.S. Puttaswamy v. Union of India (2017) held that privacy is a fundamental right, part of life and personal liberty under Article 21, and of the freedoms in Part III as a whole. The bench overruled M.P. Sharma (1954) and Kharak Singh (1962) on this point. Article 15 (a) bars discrimination. Article 19 (b) protects six freedoms, such as speech. Article 29 (d) protects the culture of minorities.
Notice the follow-ups: the Aadhaar judgment (2018), which upheld Aadhaar with limits, and the Digital Personal Data Protection Act, 2023, whose rules were notified in 2025. Privacy, like other rights, can be limited by a fair law.
Article 19 looks right because privacy feels like a "freedom". The Court rooted it mainly in Article 21.
UPSC repeats traps like this year after year. The PYQ Book gathers every trap in one place, so you see them coming. Try the free sample
Answer as per the official UPSC answer key.
A biology class at high school predicted that a local population of animals will double in size every 12 years. The population at the beginning of the year 2021 was estimated to be 50 animals. If P represents the population after n years, then which one of the following equations represents the model of the class for the population ?
Answer (d) & explanation
The model is P = 50(2)^(n/12) (d). Step 1: doubling means multiplying, not adding. So the linear options (a) and (b) are out. Step 2: after 12 years, there should be exactly one doubling. Put n = 12: 2^(12/12) = 2¹ = 2, so P = 100. Correct. Step 3: option (c), 2^(12n), at n = 12 gives 2¹⁴⁴, which is absurdly large. So only (d) fits. After 24 years, (d) gives 50 × 4 = 200, again correct.
Tip: for growth that doubles every T years, use P = P₀ × 2^(n/T). Test an easy value of n to check any formula quickly.
Answer as per the official UPSC answer key.