UPSC Prelims PYQs with explanations
Real questions from official papers, mapped to syllabus topics. Attempt each one; the answer and the reason appear instantly.
What is the importance of the term "Interest Coverage Ratio" of a firm in India ?
- 1. It helps in understanding the present risk of a firm that a bank is going to give loan to.
- 2. It helps in evaluating the emerging risk of a firm that a bank is going to give loan to.
- 3. The higher a borrowing firm's level of Interest Coverage Ratio, the worse is its ability to service its debt.
Select the correct answer using the code given below :
Answer (a) & explanation
Statements 1 and 2 are correct (a). The Interest Coverage Ratio = earnings before interest and tax (EBIT) divided by the interest payable. It shows how many times a firm's profit covers its interest bill. Statement 1 is right because banks use it to judge a borrower's present risk. Statement 2 is right because a falling ratio warns of emerging risk before the firm defaults. Statement 3 is wrong because a higher ratio means a better, not worse, ability to service debt. A ratio below 1 means the firm cannot meet its interest from its earnings.
Notice related ratios: the debt-to-equity ratio and the Debt Service Coverage Ratio. Firms with a ratio below 1 for years are often called "zombie" companies.
Answer as per the official UPSC answer key.
With reference to chemical fertilizers in India, consider the following statements :
- 1. At present, the retail price of chemical fertilizers is market-driven and not administered by the Government.
- 2. Ammonia, which is an input of urea, is produced from natural gas.
- 3. Sulphur, which is a raw material for phosphoric acid fertilizer, is a by-product of oil refineries.
Which of the statements given above is/are correct ?
Answer (b) & explanation
Statements 2 and 3 are correct (b). Statement 1 is wrong: the retail price of urea is fixed by the government (about ₹242 for a 45 kg bag), and P and K fertilisers get a fixed subsidy under Nutrient Based Subsidy (2010), so prices are not purely market-driven. Statement 2 is right: ammonia, the input for urea, is made mostly from natural gas, much of it imported as LNG. Statement 3 is right: sulphur recovered from oil refining is used to make sulphuric acid, which then makes phosphoric acid for DAP.
Notice neem-coated urea (100% since 2015) and nano urea from IFFCO. Fertiliser subsidy is among the biggest items in the Union budget.
Answer as per the official UPSC answer key.
Read the passage
Private investment in general is volatile. Foreign private investment is more volatile because the available investment avenues are significantly greater (i.e., the entire world). Therefore, the responsibility of providing employment cannot be left to Foreign Direct Investment (FDI). The current FDI inflows are volatile over time and, across sectors and regions, which is a necessary consequence of their search for the highest returns. The adverse consequences are unstable employment and an accentuation of income and regional inequalities. A probable positive consequence of foreign investment is the inflow of new technology and its subsequent diffusion. However, the technology diffusion is not at all certain because the existing state of physical and human capital in India may prove inadequate for the diffusion.
With reference to the above passage, the following assumptions have been made :
- 1. Relying on foreign investment in the long run is not an economically sound policy.
- 2. Policies must be undertaken to reduce volatility in foreign private investment.
- 3. Policies must be undertaken to strengthen domestic private investment.
- 4. Public investment should be given priority over private investment.
- 5. Substantial public investment in education and health should be undertaken.
Which of the above assumptions is/are valid?
Answer (b) & explanation
Assumptions 1, 3 and 5 are valid (b). Step 1: the passage says jobs "cannot be left to FDI". So relying on foreign investment in the long run is unwise (1), and domestic private investment must be strengthened (3). Step 2: it says weak human capital blocks the spread of technology. So spending on education and health is needed (5). Step 3: assumption 2 fails because the passage calls FDI volatility a "necessary consequence", which policy cannot remove. Assumption 4, putting public over private investment, is not argued. So options (a), (c) and (d) fail.
Tip: if a passage calls something unavoidable, reject options that ask policy to prevent it.
Answer as per the official UPSC answer key.
The recurring decimal representation 1·272727... is equivalent to
Answer (b) & explanation
1·272727... equals 14/11 (b). Step 1: split it: 1 + 0·2727... Step 2: a two-digit repeating block over 99: 0·2727... = 27/99 = 3/11. Step 3: 1 + 3/11 = 14/11. Check: 14 ÷ 11 = 1·2727... Option (a), 13/11 = 1·1818... Option (c), 127/99 = 1·2828... Option (d), 137/99 = 1·3838... All fail.
Tip: for pure recurring decimals, put the repeating digits over as many 9s as there are digits: 0·ab ab... = ab/99. Then simplify. If one digit does not repeat, like 1·2333..., use 9s for repeating digits and 0s for the rest.
Answer as per the official UPSC answer key.
Along with the Budget, the Finance Minister also places other documents before the Parliament which include 'The Macro Economic Framework Statement'. The aforesaid document is presented because this is mandated by
Answer (d) & explanation
The FRBM Act, 2003 requires it (d). Under Section 3 of the Fiscal Responsibility and Budget Management Act, the government must lay certain statements before Parliament with the Budget. These are the Macro-economic Framework Statement, which assesses growth, the fiscal balance and the external sector, and the Medium-term Fiscal Policy cum Fiscal Policy Strategy Statement. The Medium-term Expenditure Framework Statement is laid in the session after the Budget. It is not just a convention (a). Article 112 (b) requires the Annual Financial Statement, and Article 110 defines Money Bills. Article 113 (c) deals with demands for grants.
Notice the targets: the government set a 4.4% fiscal deficit target for 2025–26, and is shifting to a debt-to-GDP anchor of about 50% by 2031.
Answer as per the official UPSC answer key.
With reference to carbon nanotubes, consider the following statements :
- 1. They can be used as carriers of drugs and antigens in the human body.
- 2. They can be made into artificial blood capillaries for an injured part of human body.
- 3. They can be used in biochemical sensors.
- 4. Carbon nanotubes are biodegradable.
Which of the statements given above are correct ?
Answer (c) & explanation
Statements 1, 3 and 4 are correct (c). Carbon nanotubes are tiny tubes of carbon atoms, like rolled sheets of graphene. They are very strong, light and good conductors. Statement 1 is right because they are studied as carriers of drugs and antigens (for vaccines) into cells. Statement 3 is right because they are used in biochemical sensors, for example to detect glucose or disease markers. Statement 4 is right because research has shown that enzymes such as myeloperoxidase, found in white blood cells, can break them down. Statement 2 is wrong in UPSC's key, as artificial capillaries made from them are not established.
Notice the concerns: some long nanotubes behave like asbestos in the lungs. Sumio Iijima described them in 1991.
Answer as per the official UPSC answer key.
Which of the following Protected Areas are located in Cauvery basin ?
- 1. Nagarhole National Park
- 2. Papikonda National Park
- 3. Sathyamangalam Tiger Reserve
- 4. Wayanad Wildlife Sanctuary
Select the correct answer using the code given below :
Answer (c) & explanation
Nagarhole, Sathyamangalam and Wayanad lie in the Cauvery basin (c). All three sit in the Nilgiri hill region, drained by Cauvery tributaries. Item 1 is right: Nagarhole (Karnataka) is drained by the Kabini. Item 3 is right: Sathyamangalam (Tamil Nadu) lies along the Moyar and Bhavani. Item 4 is right: Wayanad (Kerala) is drained by the Kabini and its streams. Item 2 is wrong: Papikonda National Park is on the Godavari in Andhra Pradesh, where the river cuts a gorge through the Eastern Ghats.
Notice the Nilgiri Biosphere Reserve (1986), India's first, which links Nagarhole, Bandipur, Mudumalai, Wayanad and Silent Valley. Other Cauvery tributaries include the Hemavati, Shimsha, Arkavathi and Amaravati.
Answer as per the official UPSC answer key.
Which of the following statements correctly explains the impact of Industrial Revolution on India during the first half of the nineteenth century ?
Answer (a) & explanation
Indian handicrafts were ruined (a). After the Charter Act of 1813 ended the Company's trade monopoly, cheap machine-made British cloth flooded India under one-way free trade. British goods entered India with very low duties, while Indian goods faced high duties in Britain. This ruined Indian handicrafts, especially weaving, and towns such as Dhaka, Murshidabad and Surat declined. This process is called deindustrialisation. Option (b) is wrong because the first cotton mill came only in 1854. Option (c) is wrong because railways began only in 1853. Option (d) is wrong because duties on British imports were very low.
Notice the result: millions of artisans moved to farming, adding to pressure on land. Dadabhai Naoroji's Drain Theory and R.C. Dutt described this.
Answer as per the official UPSC answer key.
Two Statements are given followed by two Conclusions :
Statements : All numbers are divisible by 2. All numbers are divisible by 3.
Conclusion-I : All numbers are divisible by 6.
Conclusion-II : All numbers are divisible by 4.
Which of the above Conclusions logically follows/follow from the two given Statements?
Answer (a) & explanation
Only Conclusion I follows (a). Step 1: all numbers are divisible by 2 and by 3. Since 2 and 3 share no common factor, a number divisible by both is divisible by 2 × 3 = 6. So Conclusion I follows. Step 2: Conclusion II says all are divisible by 4. But being divisible by 2 does not mean divisible by 4. For example, 6 is divisible by 2 and 3, but not by 4. Step 3: so II does not follow. Options (b), (c) and (d) fail.
Tip: if a number is divisible by two co-prime numbers (no shared factor), it is divisible by their product. This does not work for 2 and 4, which share a factor.
Answer as per the official UPSC answer key.
Read the passage
Genome editing is different from genome modification. Genome editing typically involves finding the part of a plant genome that could be changed to render it less vulnerable to disease, or resistant to certain herbicides, or to increase yields. Researchers use ‘molecular scissors’ to dissect the genome and repair it, which is a process that occurs naturally when plants are under attack from diseases and can throw up new mutations that enable the plant to survive future attacks. This evolutionary process can effectively be speeded up now that it is possible to examine plant genomes in detail in laboratories, and create mechanisms through which the relevant genes can be altered very precisely.
With reference to the above passage, the following assumptions have been made :
- 1. Genome editing does not require the transfer of genes from one plant to another.
- 2. Through genome editing, the chosen genes can be altered precisely in a manner akin to the natural process that helps plants to adapt to the environmental factors.
Which of the above assumptions is/are valid?
Answer (c) & explanation
Both assumptions are valid (c). Step 1: the passage says genome editing changes a plant's own genes, unlike genetic modification, which moves genes from another organism. So editing does not need gene transfer (1). Step 2: it says editing speeds up a natural repair process and works "very precisely". So chosen genes can be changed precisely, much like nature's own way of adapting (2). Step 3: so options (a), (b) and (d) fail.
Tip: CRISPR is the best-known gene-editing tool. In May 2025, India released two genome-edited rice varieties, DRR Dhan 100 (Kamala) and Pusa DST Rice 1, the world's first such rice varieties.
Answer as per the official UPSC answer key.
With reference to the provisions contained in Part IV of the Constitution of India, which of the following statements is/are correct?
- 1. They shall be enforceable by courts.
- 2. They shall not be enforceable by any court.
- 3. The principles laid down in this part are to influence the making of laws by the State.
Select the correct answer using the code given below :
Answer (d) & explanation
Statements 2 and 3 are correct (d). Article 37 says the Directive Principles in Part IV shall not be enforceable by any court (2). But they are "fundamental in the governance of the country", and the State must apply them in making laws (3). Statement 1 is wrong because they cannot be enforced by courts. This is the main difference from the Fundamental Rights, which can be enforced under Article 32.
Courts have still used DPSPs to interpret rights. In Minerva Mills (1980), the Court said a balance between Fundamental Rights and DPSPs is part of the basic structure. Notice how Article 21A (education) and many welfare laws came from DPSPs. The idea came from Ireland's Constitution.
Answer as per the official UPSC answer key.
With reference to the international trade of India at present, which of the following statements is/are correct ?
- 1. India's merchandise exports are less than its merchandise imports.
- 2. India's imports of iron and steel, chemicals, fertilisers and machinery have decreased in recent years.
- 3. India's exports of services are more than its imports of services.
- 4. India suffers from an overall trade/current account deficit.
Select the correct answer using the code given below :
No official answer (question dropped) & notes
UPSC dropped this question, so no answer was scored. The likely reason is statement 4: India usually runs a current account deficit, but in 2020–21 it posted a small surplus as imports collapsed during COVID. The lasting facts are clear. Statement 1 is right: India's merchandise imports (crude oil, gold, electronics) exceed its exports, giving a large trade deficit. Statement 3 is right: India has a big services surplus from software and IT exports. Statement 2 is wrong: imports of iron and steel, chemicals, fertilisers and machinery have generally risen, not fallen.
Notice the full balance of payments: the current account (goods, services, remittances) and the capital account (FDI, FPI, loans). India is the world's largest receiver of remittances.
UPSC did not evaluate this question, so no official answer exists. Use it for practice only.
UPSC dropped this question from evaluation; there is no official answer.
According to India's National Policy on Biofuels, which of the following can be used as raw materials for the production of biofuels ?
- 1. Cassava
- 2. Damaged wheat grains
- 3. Groundnut seeds
- 4. Horse gram
- 5. Rotten potatoes
- 6. Sugar beet
Select the correct answer using the code given below :
Answer (a) & explanation
Cassava, damaged wheat, rotten potatoes and sugar beet are allowed (a). The National Policy on Biofuels, 2018 widened the raw materials for ethanol. It allows sugarcane juice, sugar beet and sweet sorghum (sugar crops); cassava, corn and other starchy crops; damaged food grains such as wheat and broken rice unfit for eating; and rotten potatoes. So items 1, 2, 5 and 6 are right. Items 3 and 4 are wrong: groundnut (an oilseed) and horse gram (a pulse) are food crops that are not on the list.
Notice the 2022 amendment, which advanced the target of 20% ethanol blending in petrol (E20) to 2025–26; India reached about 20% in 2025. Second-generation (2G) ethanol uses crop waste such as straw.
Answer as per the official UPSC answer key.
In the sum
⊗ + 1⊗ + 5⊗ + ⊗⊗ + ⊗1 = 1⊗⊗
for which digit does the symbol ⊗ stand?
Answer (b) & explanation
The symbol stands for 3 (b). Step 1: test the options. Put ⊗ = 3. Step 2: left side: 3 + 13 + 53 + 33 + 31 = 133. Step 3: right side: 1⊗⊗ = 133. Both sides match, so ⊗ = 3. Check another: ⊗ = 2 gives 2 + 12 + 52 + 22 + 21 = 109, but 1⊗⊗ = 122. No match. Options (a), (c) and (d) fail.
Tip: when an equation has one unknown digit and four options, plugging in is quickest. Algebra also works: the left side is 24⊗ + 61 and the right side is 100 + 11⊗, so 13⊗ = 39 and ⊗ = 3.
Trying the four options is quicker than any algebra here.
Answer as per the official UPSC answer key.
Read the passage
The pulse variety ‘Pusa Arhar 16’ has the potential to be grown in the paddy-growing regions of Punjab, Haryana and Uttar Pradesh and eventually in all of India. Its yield (about 2000 kg/hectare) will be significantly greater than those of the existing varieties and because its size will be uniform, it will be amenable to mechanical harvesting, an attractive feature for farmers in northern India who currently use this technology for paddy. Most important, Arhar straw, unlike paddy straw, is green and can be ploughed back into the soil. In paddy straw, the problem is the high silica content, which does not allow for easy decomposition. In the case of Arhar, the farmer, even after combine harvesting, just needs to run a rotovator to cut the leftover straw into pieces, which can be ploughed back and will decompose very fast. All this is difficult with leftover paddy stalks that cannot be easily salvaged or ploughed back. Farmers, therefore, choose the easiest option of simply burning it.
Which of the following are the most rational inferences that can be made from the passage?
- 1. Farmers’ income will be higher with pulse cultivation than with paddy cultivation.
- 2. Pulse cultivation causes less pollution as compared to paddy cultivation.
- 3. Pulse straw can be used to improve soil quality.
- 4. In the context of northern Indian agriculture, paddy straw has no usefulness.
- 5. Mechanized agriculture is the main cause for stubble burning.
Select the correct answer using the code given below.
Answer (c) & explanation
Inferences 2 and 3 only (c). Step 1: the passage says arhar (pulse) straw is ploughed back into the soil and decomposes. So pulse straw improves soil (3). Step 2: paddy straw is burnt, causing smoke. So pulses cause less pollution than paddy (2). Step 3: statement 1, farmers' income, is not compared. Statement 4, paddy straw has no use, is too absolute. Statement 5 fails: the passage says paddy straw is burnt because of its high silica, not because of mechanisation. So options (a), (b) and (d) fail.
Tip: stubble burning in Punjab and Haryana adds to Delhi's winter smog. In CSAT, though, use the passage's stated reason, here silica.
Answer as per the official UPSC answer key.
How many pairs of natural numbers are there such that the difference of whose squares is 63?
Answer (a) & explanation
There are 3 such pairs (a). Step 1: x² − y² = (x − y)(x + y) = 63. Both factors must be odd, because 63 is odd, and x + y is the larger factor. Step 2: factor pairs of 63: 1 × 63, 3 × 21, 7 × 9. Step 3: solve each. 1 and 63: x = 32, y = 31. 3 and 21: x = 12, y = 9. 7 and 9: x = 8, y = 1. That is 3 pairs. Check: 64 − 1 = 63. Options (b), (c) and (d) miscount.
Tip: for x² − y² = N, count the factor pairs of N with the same parity (both odd or both even). Each gives one solution.
Answer as per the official UPSC answer key.
With reference to the cultural history of India, which one of the following is the correct description of the term ‘paramitas’ ?
Answer (c) & explanation
Paramitas are perfections on the bodhisattva path (c). In Mahayana Buddhism, the paramitas are the "perfections" that a bodhisattva practises on the way to Buddhahood. The six classic ones are dana (generosity), shila (morality), kshanti (patience), virya (effort), dhyana (meditation) and prajna (wisdom). They are sometimes extended to ten. The Prajnaparamita sutras, which include the Heart Sutra, are named after the last. Option (a) describes the Dharmasutras. Option (b) describes the nastika schools, such as Buddhism, Jainism and Charvaka. Option (d) describes guilds such as the Ayyavole (Ainnurruvar) and Manigramam.
Notice Nagarjuna, who founded the Madhyamaka school and taught at Nagarjunakonda and Amaravati in Andhra.
Answer as per the official UPSC answer key.
Which of the following factors/policies were affecting the price of rice in India in the recent past ?
- 1. Minimum Support Price
- 2. Government's trading
- 3. Government's stockpiling
- 4. Consumer subsidies
Select the correct answer using the code given below :
Answer (d) & explanation
All four affect rice prices (d). The government shapes the rice market at every step. Item 1 is right: the Minimum Support Price sets a floor for farmers and lifts market prices. Item 2 is right: government trading, such as open-market sales by FCI and export curbs (like the 2023 ban on non-basmati white rice exports), changes supply in the market. Item 3 is right: stockpiling by the Food Corporation of India takes grain off the market and keeps buffer stocks. Item 4 is right: consumer subsidies through the PDS lower what poor buyers pay and reduce market demand.
Notice the National Food Security Act, 2013, and PM Garib Kalyan Anna Yojana, which now gives free grain to about 81 crore people.
Answer as per the official UPSC answer key.
With reference to India’s Desert National Park, which of the following statements are correct ?
- 1. It is spread over two districts.
- 2. There is no human habitation inside the Park.
- 3. It is one of the natural habitats of Great Indian Bustard.
Select the correct answer using the code given below :
Answer (c) & explanation
Statements 1 and 3 are correct (c). Statement 1 is right: Desert National Park covers parts of Jaisalmer and Barmer districts in Rajasthan, about 3,162 sq km. Statement 2 is wrong: several villages and herders' settlements lie inside the park, which makes conservation harder. Statement 3 is right: it is the last major stronghold of the Great Indian Bustard, which is Critically Endangered with only about 150 birds left in the wild.
Notice the main threat to the bustard: collisions with overhead power lines, which led the Supreme Court to order lines to go underground in key areas. The park also holds fossils at Akal Wood Fossil Park. The bustard is the state bird of Rajasthan.
Answer as per the official UPSC answer key.
Read the passage
Many opportunities to harness the highly skewed, seasonal and spatial distribution of monsoon flows, which occur in a four-month period from June to September annually, have been lost. Since these few months account for most of the rainfall and consequent freshwater availability, the need for holding rainwater in reservoirs, for subsequently releasing it for use over the year, is a necessity nobody can afford to overlook. Climate change will continue to affect weather conditions and create water shortages and excesses. While millions suffer from droughts and floods, waters in the country’s many rivers flow unutilized, and are discharged into the sea every year.
With reference to the above passage, which of the following could be the most rational and practical implications for India?
- 1. Inter-linking of rivers should be undertaken.
- 2. A network of dams and canals should be built across the country for proper distribution of water.
- 3. Farmers should be provided easy loans for digging borewells.
- 4. Usage of water for agriculture should be regulated by law.
- 5. Distribution of river water among regions should be regulated by the Union Government.
Select the correct answer using the code given below.
Answer (a) & explanation
Implications 1 and 2 are rational and practical (a). Step 1: the passage says monsoon water should be stored in reservoirs and moved from flood-hit to drought-hit areas, instead of flowing into the sea. This points to inter-linking rivers (1) and a network of dams and canals (2). Step 2: statement 3, loans for borewells, would pull more groundwater; the passage does not suggest it. Step 3: statement 4, a law on farm water use, and statement 5, Union control of river sharing, are not discussed. So options (b), (c) and (d) fail.
Tip: India's Ken–Betwa link, whose foundation stone was laid in December 2024, is the first project under the national river-linking plan.
Answer as per the official UPSC answer key.