UPSC Prelims PYQs with explanations
Real questions from official papers, mapped to syllabus topics. Attempt each one; the answer and the reason appear instantly.
Jay and Vijay spent an equal amount of money to buy some pens and special pencils of the same quality from the same store. If Jay bought 3 pens and 5 pencils, and Vijay bought 2 pens and 7 pencils, then which one of the following is correct ?
Answer (c) & explanation
A pen costs twice as much as a pencil (c). Step 1: both spent the same amount. So 3 pens + 5 pencils = 2 pens + 7 pencils. Step 2: take away 2 pens and 5 pencils from both sides. What is left: 1 pen = 2 pencils. Step 3: so a pen costs two times a pencil. Option (a) reverses it; option (b), equal prices, and option (d), three times, do not fit the equation.
Tip: when two purchases cost the same, cancel the common items. What remains is a direct price comparison, with no need for algebra.
Answer as per the official UPSC answer key.
With reference to 'Urban Cooperative Banks' in India, consider the following statements :
- 1. They are supervised and regulated by local boards set up by the State Governments.
- 2. They can issue equity shares and preference shares.
- 3. They were brought under the purview of the Banking Regulation Act, 1949 through an Amendment in 1966.
Which of the statements given above is/are correct?
Answer (b) & explanation
Statements 2 and 3 are correct (b). Statement 1 is wrong: no local boards regulate Urban Cooperative Banks. They have dual control: the State Registrar of Cooperative Societies handles registration and management, and the RBI regulates their banking business. Statement 2 is right: the 2020 amendment to the Banking Regulation Act allowed UCBs to raise capital through equity shares, preference shares and bonds, with RBI approval. Statement 3 is right: cooperative banks came under the Banking Regulation Act through an amendment in 1966.
Notice the PMC Bank crisis of 2019, which pushed the 2020 amendment giving the RBI more power over cooperative banks. Multi-State cooperative banks are registered under the Central Registrar instead.
Answer as per the official UPSC answer key.
Consider the following pairs :
| Historical place | Well-known for
| 1. Burzahom | Rock-cut shrines
| 2. Chandra-ketugarh | Terracotta art
| 3. Ganeshwar | Copper artefacts
Which of the pairs given above is/are correctly matched?
Answer (d) & explanation
Pairs 2 and 3 are correct (d). Pair 1 is wrong: Burzahom in Kashmir is a Neolithic site known for pit dwellings and the burial of dogs with their masters, not rock-cut shrines. Pair 2 is right: Chandraketugarh in West Bengal, near Kolkata, is famous for fine terracotta plaques and figures from the Maurya to Gupta periods. Pair 3 is right: Ganeshwar in Sikar, Rajasthan, had a copper culture near the Khetri mines that supplied copper tools to the Harappans.
Notice other Neolithic sites: Gufkral in Kashmir, Chirand in Bihar and Mehrgarh in Pakistan. Notice too Daimabad in Maharashtra, famous for its bronze chariot.
Answer as per the official UPSC answer key.
Water can dissolve more substances than any other liquid because
Answer (a) & explanation
Water dissolves so much because it is dipolar (a). A water molecule is polar, or dipolar: the oxygen end carries a slight negative charge, and the two hydrogen ends carry slight positive charges. These partial charges surround ions and other polar molecules and pull them apart, so water dissolves more substances than any other liquid. That is why it is called the "universal solvent". Options (b) and (c) are true of water but do not explain dissolving. Option (d) is true, but being an oxide of hydrogen is not the reason.
Notice water's other special traits: high specific heat, which moderates climate; hydrogen bonding; and ice being less dense than liquid water, so it floats.
Answer as per the official UPSC answer key.
Who among the following was associated as Secretary with Hindu Female School which later came to be known as Bethune Female School?
Answer (c) & explanation
Ishwar Chandra Vidyasagar was its secretary (c). J. E. D. Bethune founded the Hindu Female School in Calcutta in 1849, and Ishwar Chandra Vidyasagar served as its secretary. It later became the Bethune School and Bethune College. Vidyasagar went on to set up 35 or more girls' schools in Bengal, and his campaign led to the Hindu Widows' Remarriage Act of 1856. Option (a) is wrong: Annie Besant came to India only in 1893. Option (b) is wrong: Debendranath Tagore led the Brahmo Samaj. Option (d) is wrong: Sarojini Naidu was born in 1879.
Notice Vidyasagar's Bengali primer Barnaparichay. Bethune College's early students included Kadambini Ganguly, among India's first women graduates.
Answer as per the official UPSC answer key.
Read the passage
It is certain, that seditions, wars, and contempt or breach of the laws are not so much to be imputed to the wickedness of the subjects, as to the bad state of a dominion. For men are not born fit for citizenship, but must be made so. Besides, men’s natural passions are everywhere the same; and if wickedness more prevails, and more offences are committed in one commonwealth than in another, it is certain that the former has neither enough pursued the end of unity, nor framed its laws with sufficient forethought; and that, therefore, it has failed in making quite good its right as a commonwealth.
Which among the following is the most logical and rational inference that can be made from the passage given above ?
Answer (c) & explanation
The best inference is that the best dominion pursues unity and has laws for good citizenship (c). Step 1: the passage says trouble comes from a state that has not pursued the end of unity nor framed laws with forethought. So a good state does both. That is (c). Step 2: option (b) says the sovereign is responsible for all problems. But the passage says "not so much" the subjects, which is softer. Step 3: option (a) calls wars inevitable, and option (d) calls a good state impossible. The passage says the opposite: men can be "made" fit for citizenship.
Tip: watch for absolute words like "all", "inevitable" and "impossible". The passage's mild wording ("not so much") rarely supports them.
Answer as per the official UPSC answer key.
On a chess board, in how many different ways can 6 consecutive squares be chosen on the diagonals along a straight path ?
Answer (b) & explanation
There are 6 ways (b). Step 1: a chess board has two main diagonals with 8 squares each. Step 2: a straight run of 6 squares on a diagonal of 8 can start at square 1, 2 or 3. That gives 3 ways on each diagonal. Step 3: two diagonals × 3 = 6. Option (a), 4, and the bigger options (c) 8 and (d) 12 do not match this count. UPSC's key counts only the two main diagonals here.
Tip: the number of runs of length k in a line of n squares is n − k + 1. Here 8 − 6 + 1 = 3.
Answer as per the official UPSC answer key.
‘R2 Code of Practices’ constitutes a tool available for promoting the adoption of
Answer (a) & explanation
R2 promotes responsible electronics recycling (a). R2, short for "Responsible Recycling", is a certification standard for firms that repair, refurbish and recycle electronics. It covers the safe handling of e-waste, data security when old devices are wiped, worker health and safety, and tracking of materials through the recycling chain. Option (b) is a trap: the "R" stands for recycling, not Ramsar. Option (c) is wrong: it does not deal with crops on degraded land. Option (d) is wrong: it is not an EIA tool.
Notice India's E-Waste (Management) Rules, 2022, based on Extended Producer Responsibility (EPR). India is among the world's top three e-waste producers, after China and the US.
Answer as per the official UPSC answer key.
Consider the following statements :
- 1. 21st February is declared to be the International Mother Language Day by UNICEF.
- 2. The demand that Bangla has to be one of the national languages was raised in the Constituent Assembly of Pakistan.
Which of the above statements is/are correct?
Answer (b) & explanation
Only statement 2 is correct (b). Statement 1 is wrong: UNESCO, not UNICEF, declared 21 February as International Mother Language Day in 1999. The date marks the students killed by police in Dhaka on 21 February 1952 during the Bhasha Andolan (Language Movement). Statement 2 is right: in February 1948, Dhirendranath Datta asked the Constituent Assembly of Pakistan to accept Bangla as a state language beside Urdu and English.
Notice that the language movement fed Bengali nationalism, which led to the creation of Bangladesh in 1971. Bangla became a state language of Pakistan in 1956. The Shaheed Minar in Dhaka honours the martyrs.
UNICEF and UNESCO are a standard swap. Culture and language days come from UNESCO.
Answer as per the official UPSC answer key.
With reference to India, consider the following statements :
- 1. Judicial custody means an accused is in the custody of the concerned magistrate and such accused is locked up in police station, not in jail.
- 2. During judicial custody, the police officer in charge of the case is not allowed to interrogate the suspect without the approval of the court.
Which of the statements given above is/are correct?
Answer (b) & explanation
Only statement 2 is correct (b). Statement 1 is wrong: in police custody, the accused is held in a police lock-up; in judicial custody, he is in jail under the magistrate's control, not in a police station. Statement 2 is right: during judicial custody, the police can question the suspect only with the court's permission. Police custody is limited to 15 days in total, within the first part of the remand period.
Notice that the Bharatiya Nagarik Suraksha Sanhita (BNSS, 2023), which replaced the CrPC from 1 July 2024, lets the 15 days of police custody be taken in parts during the first 40 or 60 days. D.K. Basu (1997) laid down guidelines on arrest and custody.
Answer as per the official UPSC answer key.
Read the passage
Fig trees (genus Ficus) are considered sacred in India, East Asia and Africa and are common in agricultural and urban landscapes where other large trees are absent. In natural forests, fig trees provide food for wildlife when other resources are scarce and support a high density and diversity of frugivores (fruit-eating animals). If frugivorous birds and bats continue to visit fig trees located in sites with high human disturbance, sacred fig trees may promote frugivore abundance. Under favourable microclimate, plenty of seedlings of other tree species would grow around fig trees.
On the basis of the passage given above, the following assumptions have been made :
- 1. Fig trees can often be keystone species in natural forests.
- 2. Fig trees can grow where other large woody species cannot grow.
- 3. Sacred trees can have a role in biodiversity conservation.
- 4. Fig trees have a role in the seed dispersal of other tree species.
Which of the above assumptions is/are valid ?
Answer (a) & explanation
Assumptions 1 and 2 are valid (a). Step 1: the passage says figs feed wildlife "when other resources are scarce". A plant that keeps many animals alive is a keystone species (1). Step 2: it says figs grow where other large trees are absent. So they can grow where other woody species cannot (2). Step 3: UPSC's key treats statement 3, sacred trees aiding conservation, as only conditional in the passage. Statement 4, seed dispersal of other trees, is unstated. So options (b), (c) and (d) fail.
Tip: a keystone species is one whose loss would collapse much of its ecosystem. Figs, which fruit all year, are a classic example in Indian forests.
Answer as per the official UPSC answer key.
Read the passage
The resolution of bankruptcy cases of Indian banks under the Insolvency and Bankruptcy Code should help bring non-performing assets (NPA) situation under some control. Despite the slow pace of resolutions by the National Company Law Tribunal, the Code can be helpful in cleaning up bank books in future credit cycles. The recapitalisation of public sector banks too can help increase the capital cushion of banks and induce them to lend more and boost economic activity. But bad debt resolution and recapitalisation are only a part of the solution as they, by themselves, can do very little to rein in reckless lending that has pushed the Indian banking system to its current sorry state. Unless there are systemic reforms that address the problem of unsustainable lending, future credit cycles will continue to stress the banking system.
Which one of the following statements best reflects the most logical, rational and practical suggestion implied by the passage given above ?
Answer (d) & explanation
The suggestion is that Indian banking needs structural reforms as the long-term answer to bad loans (d). Step 1: the passage says bad-debt resolution and recapitalisation are "only a part of the solution". Step 2: it ends: unless there are "systemic reforms" to stop unsustainable lending, future credit cycles will stress banks. That is (d). Step 3: option (a), government monitoring of lending, and option (c), mergers, are specific steps the passage never proposes. Option (b), low interest rates to boost lending, goes against the passage's worry about reckless lending.
Tip: the last line of a passage often carries its suggestion. Here "unless there are systemic reforms" points straight to (d).
Answer as per the official UPSC answer key.
Joseph visits the club on every 5th day, Harsh visits on every 24th day, while Sumit visits on every 9th day. If all three of them met at the club on a Sunday, then on which day will all three of them meet again ?
Answer (b) & explanation
They meet again on a Wednesday (b). Step 1: they meet again after the LCM of 5, 24 and 9. 24 = 2³ × 3 and 9 = 3², so the LCM = 2³ × 3² × 5 = 360 days. Step 2: find the weekday shift: 360 ÷ 7 = 51 weeks and 3 days left over. Step 3: Sunday + 3 days = Wednesday. Option (d), Sunday, ignores the extra days. Options (a) and (c) miscount.
Tip: "every nth day" problems use the LCM. Then divide by 7 and use the remainder to move the weekday forward.
Answer as per the official UPSC answer key.
In case of which one of the following biogeochemical cycles, the weathering of rocks is the main source of release of nutrient to enter the cycle?
Answer (c) & explanation
The phosphorus cycle depends on rock weathering (c). The phosphorus cycle has no important gas phase. Phosphorus is locked in rocks as phosphate minerals and enters soil and water only as rocks weather. Plants take it up, animals eat the plants, and it returns to soil and the sea when they die, finally settling as sediment that becomes rock again. Option (a) is wrong: carbon cycles mainly through the air as CO₂. Option (b) is wrong: nitrogen enters mainly from the air through fixation. Option (d) is wrong: sulphur has both rock and gas sources, such as volcanoes and SO₂.
Notice that phosphorus is often the limiting nutrient in lakes, and excess phosphate from fertilisers and detergents causes eutrophication.
sulphur also comes from rocks, but it has a large gas phase (SO2, H2S). Phosphorus has none.
Answer as per the official UPSC answer key.
The vegetation of savannah consists of grassland with scattered small trees, but extensive areas have no trees. The forest development in such areas is generally kept in check by one or more or a combination of some conditions. Which of the following are such conditions?
- 1. Burrowing animals and termites
- 2. Fire
- 3. Grazing herbivores
- 4. Seasonal rainfall
- 5. Soil properties
Select the correct answer using the code given below.
Answer (c) & explanation
Fire, grazing and seasonal rainfall keep savannahs open (c). Savannahs are grasslands with scattered trees. Item 2 is right: frequent fires in the dry season kill young trees, while grasses regrow from their roots. Item 3 is right: grazing and browsing animals, such as zebras, antelopes and elephants, eat young trees and shrubs. Item 4 is right: seasonal rainfall, with a long dry season, limits tree growth. Items 1 and 5 can play a part locally, but they are not the standard explanation, and only option (c) groups the three main conditions.
Notice that the largest savannahs are in Africa, such as the Serengeti. In South America they are called llanos and campos. India's tropical grasslands include the Banni of Kachchh.
Answer as per the official UPSC answer key.
Consider the following statements in respect of Bharat Ratna and Padma Awards :
- 1. Bharat Ratna and Padma Awards are titles under the Article 18(1) of the Constitution of India.
- 2. Padma Awards, which were instituted in the year 1954, were suspended only once.
- 3. The number of Bharat Ratna Awards is restricted to a maximum of five in a particular year.
Which of the above statements are not correct?
Answer (d) & explanation
All three statements are not correct (d). Statement 1 is wrong: in Balaji Raghavan v. Union of India (1995), the Supreme Court held that the Bharat Ratna and Padma awards are not titles under Article 18(1), so they cannot be used as prefixes or suffixes to names. Statement 2 is wrong: the awards were suspended twice, in 1977–80 and 1992–98. Statement 3 is wrong: the Bharat Ratna is normally limited to three a year, not five; 2024 was an exception, with five awards, including Karpoori Thakur and M.S. Swaminathan.
Notice that both awards were instituted in 1954. The Padma awards have three grades: Padma Vibhushan, Padma Bhushan and Padma Shri, announced on the eve of Republic Day.
the question asks for statements that are not correct. Circle "not" before you start.
Answer as per the official UPSC answer key.
Read the passage
There are reports that some of the antibiotics sold in the market are fed to poultry and other livestock as growth promoters. Overusing these substances can create superbugs, pathogens that are resistant to multiple drugs and could be passed along humans. Mindful of that, some farming companies have stopped using the drugs to make chickens gain weight faster. Since Denmark banned antibiotic growth promoters in the 1990s, the major pork exporter says it is producing more pigs — and the animals get fewer diseases.
Which one of the following statements best reflects the critical message conveyed by the passage given above ?
Answer (d) & explanation
The critical message is that antibiotics should only be used to treat diseases (d). Step 1: the passage objects to antibiotics used as growth promoters in farm animals. Denmark banned that use, not all use. So antibiotics should be kept for treating illness. That is (d). Step 2: option (c), banning antibiotics on animals completely, would stop treatment of sick animals too. Step 3: options (a) and (b), avoiding animal products or replacing them with plant foods, are not discussed.
Tip: overuse of antibiotics breeds drug-resistant germs (antimicrobial resistance). India's Kerala launched a state action plan against it in 2018. Choose the option matching the passage's exact objection.
Answer as per the official UPSC answer key.
P scored 40 marks more than Q in an examination. If Q scored 10% less marks than P, then how much did Q score ?
Answer (a) & explanation
Q scored 360 (a). Step 1: Q scored 10% less than P. So the gap between them is 10% of P's marks. Step 2: the gap is 40 marks. So 10% of P = 40, which gives P = 400. Step 3: Q = 400 − 40 = 360. Option (c), 400, is P's score, not Q's. Options (b) 380 and (d) 420 come from using Q as the base of the percentage.
Tip: always ask "10% of whom?". Here "less than P" means P is the base. Check: 10% of 400 is 40, and 400 − 40 = 360.
10% less than P, so the base is P, not Q.
Answer as per the official UPSC answer key.
Indian Government Bond Yields are influenced by which of the following?
- 1. Actions of the United States Federal Reserve
- 2. Actions of the Reserve Bank of India
- 3. Inflation and short-term interest rates
Select the correct answer using the code given below.
Answer (d) & explanation
All three influence Indian bond yields (d). A bond yield is the return investors demand for holding a bond; it moves opposite to the bond's price. Item 1 is right: if the US Federal Reserve raises rates, US bonds pay more, foreign investors sell Indian bonds, and Indian yields rise. Item 2 is right: RBI moves on the repo rate, and its bond purchases through open market operations, move yields directly. Item 3 is right: higher inflation and higher short-term rates make investors ask for a higher return on long bonds.
Notice that Indian government bonds joined JP Morgan's emerging market bond index in 2024, which drew foreign inflows. The 10-year G-Sec yield is India's benchmark interest rate.
Answer as per the official UPSC answer key.
Consider the following statements :
- 1. It was during the reign of Iltutmish that Chengiz Khan reached the Indus in pursuit of the fugitive Khwarezm prince.
- 2. It was during the reign of Muhammad bin Tughluq that Taimur occupied Multan and crossed the Indus.
- 3. It was during the reign of Deva Raya II of Vijayanagara Empire that Vasco da Gama reached the coast of Kerala.
Which of the statements given above is/are correct?
Answer (a) & explanation
Only statement 1 is correct (a). Statement 1 is right: Chingiz Khan reached the Indus in 1221, during the reign of Iltutmish, chasing the Khwarezm prince Jalal-ud-din Mangbarni. Iltutmish wisely refused the prince shelter, saving Delhi from attack. Statement 2 is wrong: Timur invaded in 1398, in the reign of Nasir-ud-din Mahmud Tughluq, not Muhammad bin Tughluq, who died in 1351. Statement 3 is wrong: Vasco da Gama reached Calicut in 1498, long after Deva Raya II died in 1446; Vijayanagara was then under the Saluva dynasty.
Notice that Timur's sack of Delhi weakened the Sultanate, and the Sayyids followed. The Zamorin ruled Calicut when da Gama arrived.
Each statement gets the event right and puts the wrong ruler with it. Date each one.
Answer as per the official UPSC answer key.