UPSC Prelims PYQs with explanations
Real questions from official papers, mapped to syllabus topics. Attempt each one; the answer and the reason appear instantly.
Consider the following pairs :
| Commonly used/consumed materials | Unwanted or controversial chemicals likely to be found in them
| 1. Lipstick | Lead
| 2. Soft drinks | Brominated vegetable oils
| 3. Chinese fast food | Monosodium glutamate
Which of the pairs given above is/are correctly matched ?
Answer (d) & explanation
All three pairs are correct (d). Tests in several countries have found traces of lead in some lipsticks (1), a heavy metal that is toxic even in small doses. Brominated vegetable oil (BVO) was used to keep citrus flavours evenly mixed in soft drinks (2). It is banned in India, the EU and Japan, and the US FDA banned it in 2024 over thyroid concerns. Monosodium glutamate (MSG), sold as Ajinomoto, is the flavour enhancer that gives the umami taste in Chinese fast food (3). It is widely seen as safe but remains controversial.
Notice the related news: the Maggi row of 2015, when FSSAI questioned its MSG labelling and lead levels. Other food additives to know are potassium bromate (banned in bread) and trans fats.
Answer as per the official UPSC answer key.
With reference to the difference between the culture of Rigvedic Aryans and Indus Valley people, which of the following statements is/are correct ?
- 1. Rigvedic Aryans used the coat of mail and helmet in warfare whereas the people of Indus Valley Civilization did not leave any evidence of using them.
- 2. Rigvedic Aryans knew gold, silver and copper whereas Indus Valley people knew only copper and iron.
- 3. Rigvedic Aryans had domesticated the horse whereas there is no evidence of Indus Valley people having been aware of this animal.
Select the correct answer using the code given below :
Answer (c) & explanation
Statements 1 and 3 are correct (c). The Rigveda mentions armour (varman) and helmets (shipra), while no such gear has been found at Harappan sites (1). The horse is central to Rigvedic life, pulling chariots and appearing in the ashvamedha, but solid evidence of horses at Harappan sites is weak, apart from disputed finds at Surkotada (3). Statement 2 is wrong because the Harappans used gold, silver, copper, tin and bronze, but not iron. Iron came into use only around 1000 BCE, in the later Vedic period and the Painted Grey Ware culture.
The Rigvedic people knew copper and bronze (ayas). Notice the contrast between the two cultures: the Harappans were urban, while the Rigvedic people were pastoral and rural, counting wealth in cattle.
"Copper and iron" is the slip. The Harappan age is a Bronze Age.
Answer as per the official UPSC answer key.
In a city, 12% of households earn less than ₹ 30,000 per year, 6% households earn more than ₹ 2,00,000 per year, 22% households earn more than ₹ 1,00,000 per year and 990 households earn between ₹ 30,000 and ₹ 1,00,000 per year. How many households earn between ₹ 1,00,000 and ₹ 2,00,000 per year?
Answer (b) & explanation
240 households earn between Rs 1 lakh and Rs 2 lakh (b). Step 1: 12% earn below Rs 30,000 and 22% earn above Rs 1 lakh. So the middle group, Rs 30,000 to Rs 1 lakh, is 100 − 12 − 22 = 66%. Step 2: 66% = 990 households, so 1% = 15 households. Step 3: those above Rs 1 lakh are 22%, and those above Rs 2 lakh are 6%. So Rs 1 lakh to Rs 2 lakh = 22 − 6 = 16% = 16 × 15 = 240. Options (a), (c) and (d) do not fit.
Tip: "more than Rs 1 lakh" includes "more than Rs 2 lakh". Subtract the inner group to get the band in between.
the 6% earning over ₹ 2 lakh is inside the 22%.
Answer as per the official UPSC answer key.
Read the passage
The medium term challenge for Indian manufacturing is to move from lower to higher tech sectors, from lower to higher value-added sectors, and from lower to higher productivity sectors. Medium tech industries are primarily capital intensive and resource processing; and high tech industries are mainly capital and technology intensive. In order to push the share of manufacturing in overall GDP to the projected 25 per cent, Indian manufacturing needs to capture the global market in sectors showing a rising trend in demand. These sectors are largely high technology and capital intensive.
Which among the following is the most logical and rational inference that can be made from the above passage?
Answer (c) & explanation
India should raise public investment and encourage private investment in R&D, technology and skills (c). Step 1: the passage says sectors with rising global demand are "high technology and capital intensive". To move into them, India needs investment in research, technology and skills. That is option (c). Step 2: option (d) says India already has a big share in these sectors. That contradicts the passage's line that India "needs to capture" it. Step 3: option (b) says such industries are not possible in India, which is defeatist. Option (a) gets the facts wrong.
Tip: a good inference points to the step that fills the gap the passage names. Here the gap is technology and capital.
Answer as per the official UPSC answer key.
Consider the following statements :
With reference to the Constitution of India, the Directive Principles of State Policy constitute limitations upon
- 1. legislative function.
- 2. executive function.
Which of the above statements is/are correct?
Answer (d) & explanation
Neither statement is correct (d). Directive Principles (Part IV) are positive directions telling the State what it should do, such as securing livelihoods, equal pay and free legal aid. They are not limits on what Parliament or the government can do. Under Article 37, they are not enforceable in court, so a law cannot be struck down just for ignoring a DPSP. It is Fundamental Rights (Part III) that act as limits on both legislative and executive action, through Article 13.
Courts still use DPSPs to read laws and to judge "reasonable restrictions". In Minerva Mills (1980), the Supreme Court said the Constitution rests on the balance between Parts III and IV. Notice Granville Austin's phrase: together they are the "conscience of the Constitution".
"limitations" belongs to Part III. Part IV gives goals, not limits.
Answer as per the official UPSC answer key.
Which one of the following was a very important seaport in the Kakatiya kingdom ?
Answer (b) & explanation
Motupalli was the main Kakatiya port (b). Motupalli, in present-day Prakasam/Bapatla district, Andhra Pradesh, was the leading seaport of the Kakatiyas of Warangal. Ganapatideva left an abhaya-shasana (assurance inscription) there in 1244–45. It promised foreign merchants fair customs duties and protection from the old custom of seizing shipwrecked goods. Marco Polo came during Rudramadevi's reign and praised the region's diamonds and fine cloth. Kakinada (a) and Machilipatnam (c) became important later, Machilipatnam under the Golconda Qutb Shahis and European companies. Nellore (d) was not the Kakatiya port.
Notice the Kakatiya legacy: tank irrigation such as Ramappa and Pakhal lakes, and the Ramappa Temple, a UNESCO site since 2021.
Answer as per the official UPSC answer key.
What is the importance of developing Chabahar Port by India ?
Answer (c) & explanation
Chabahar gives India a route to Afghanistan and Central Asia that avoids Pakistan (c). Chabahar, on Iran's Gulf of Oman coast, connects India by sea and land to Afghanistan and Central Asia through the INSTC, without passing through Pakistan, which denies India transit. India sent wheat to Afghanistan this way and signed a ten-year contract in May 2024 to run the Shahid Beheshti terminal. African trade (a), ties with Arab oil producers (b), and an Iraq–India gas pipeline protected by Pakistan (d) are unrelated or unrealistic.
The US cancelled its sanctions waiver in 2025, and the extension ran out in April 2026, putting India's role at risk. Notice the rival port: Chabahar is about 170 km from China-backed Gwadar in Pakistan.
Answer as per the official UPSC answer key.
If second and fourth Saturdays and all the Sundays are taken as only holidays for an office, what would be the minimum number of possible working days of any month of any year?
Answer (b) & explanation
The minimum is 22 working days (b). Step 1: every month has exactly two "second and fourth" Saturdays. Sundays number 4 or 5. Step 2: February in a normal year has 28 days and 4 Sundays: 28 − 4 − 2 = 22. A leap-year February with 5 Sundays: 29 − 5 − 2 = 22. Step 3: a 30-day month with 5 Sundays gives 30 − 5 − 2 = 23. A 31-day month gives at least 24. So the minimum is 22. Option (a), 23, is from a 30-day month. Options (c) and (d) would need more holidays than possible.
Tip: for "minimum in any month", test the shortest month first, February, with the most Sundays it can have.
a 30-day month with 5 Sundays gives 23. February is the shortest month.
Answer as per the official UPSC answer key.
Read the passage
We live in digital times. The digital is not just something we use strategically and specifically to do a few tasks. Our very perception of who we are, how we connect to the world around us, and the ways in which we define our domains of life, labour and language are hugely structured by the digital technologies. The digital is everywhere and, like air, invisible. We live within digital systems, we live with intimate gadgets, we interact through digital media, and the very presence and imagination of the digital has dramatically restructured our lives. The digital, far from being a tool, is a condition and context that defines the shapes and boundaries of our understanding of the self, the society, and the structure of governance.
Which among the following is the most logical and essential message conveyed by the above passage?
Answer (b) & explanation
The message is that speaking of digital technologies is speaking of our life and living (b). Step 1: the passage calls the digital "a condition and context" that shapes self, society and governance. It is not just a tool; it is part of how we live. That is option (b). Step 2: option (a) says digital tools can solve all problems of governance. "All" goes too far. Step 3: option (c) says creativity cannot be expressed without digital media, and option (d) says digital is needed for mankind's existence. Both go well beyond the passage.
Tip: extreme words like "all", "cannot" and "existence of mankind" are signs of an overstated option.
Answer as per the official UPSC answer key.
Two walls and a ceiling of a room meet at right angles at a point P. A fly is in the air 1 m from one wall, 8 m from the other wall and 9 m from the point P. How many meters is the fly from the ceiling?
Answer (a) & explanation
The fly is 4 m from the ceiling (a). Step 1: put point P at the corner where the two walls and the ceiling meet. The fly's distances from the two walls and the ceiling act like three coordinates: 1, 8 and h. Step 2: the straight distance from P is found by a 3-D Pythagoras rule: 1² + 8² + h² = 9². Step 3: 1 + 64 + h² = 81, so h² = 16 and h = 4 m. Option (b), 6, and options (c) and (d) do not fit the equation.
Tip: in a box-shaped corner, distance from the corner = √(x² + y² + z²). It is just Pythagoras used twice. This idea also gives the diagonal of a room.
Answer as per the official UPSC answer key.
Consider the following statements :
- 1. The Nuclear Security Summits are periodically held under the aegis of the United Nations.
- 2. The International Panel on Fissile Materials is an organ of International Atomic Energy Agency.
Which of the statements given above is/are correct ?
Answer (d) & explanation
Neither statement is correct (d). Statement 1 is wrong because the four Nuclear Security Summits (Washington 2010, Seoul 2012, The Hague 2014, Washington 2016) were a US initiative under President Obama. They aimed to secure nuclear material against terrorists and were not UN meetings. Statement 2 is wrong because the International Panel on Fissile Materials (2006) is an independent group of experts based at Princeton University. It is not part of the IAEA. It publishes the Global Fissile Material Report.
India attended all four summits. Notice the real UN-linked bodies: the IAEA (Vienna, 1957) reports to the UN General Assembly and Security Council, and UNSC Resolution 1540 (2004) deals with weapons of mass destruction falling into the hands of non-state actors.
Answer as per the official UPSC answer key.
In the context of Indian history, the principle of ‘Dyarchy (diarchy)’ refers to
Answer (d) & explanation
Dyarchy split the subjects given to the provinces into two groups (d). The Government of India Act, 1919 brought dyarchy to the provinces. Provincial subjects were divided into reserved subjects, such as police, justice, land revenue and irrigation, which stayed with the Governor and his executive council. Transferred subjects, such as education, health, local government and agriculture, went to Indian ministers answerable to the legislature. Option (a) describes bicameralism, a separate change made by the same Act. Options (b) and (c) are not what dyarchy meant.
Dyarchy failed because ministers had no control over money. The 1935 Act ended it in the provinces and moved it to the Centre, but that part was never put into effect. Notice that the term comes from Lionel Curtis.
The 1919 Act also made the central legislature bicameral, so (a) sounds familiar. That was a different change, not dyarchy.
Answer as per the official UPSC answer key.
Recently there was a proposal to translocate some of the lions from their natural habitat in Gujarat to which one of the following sites ?
Answer (b) & explanation
The proposal was to move lions to Kuno-Palpur (b). Kuno-Palpur in Madhya Pradesh was chosen to give the Asiatic lion a second home, so that a single epidemic or disaster could not wipe out the only wild population in Gir, Gujarat. In 2018, canine distemper killed over 20 Gir lions. In 2013, the Supreme Court ordered the move, but Gujarat has never sent any lions. Corbett (a), Mudumalai (c) and Sariska (d) were not the chosen sites.
In 2022, Kuno National Park instead received cheetahs from Namibia and South Africa under Project Cheetah. The 2025 count found 891 lions in Gujarat. Notice that Gujarat is spreading lions across the Greater Gir landscape, including Barda, as its own alternative.
Answer as per the official UPSC answer key.
Read the passage
“The individual, according to Rousseau, puts his person and all his power in common under the supreme direction of the General Will and in our corporate capacity we receive each member as an indivisible part of the whole.”
In the light of the above passage, the nature of General Will is best described as
Answer (c) & explanation
The General Will is the collective good, distinct from private wills (c). Step 1: the passage says each person is "an indivisible part of the whole". So the General Will belongs to the community as one body. That is option (c). Step 2: option (a) calls it the sum of private wills. But Rousseau separates the General Will from the "will of all", which is just a sum of private interests. Step 3: option (b), what elected representatives say, is not mentioned. Option (d), material interests, is too narrow.
Tip: Rousseau's idea is that the General Will aims at the common good. A total of selfish wishes is not the same thing.
Answer as per the official UPSC answer key.
P works thrice as fast as Q, whereas P and Q together can work four times as fast as R. If P, Q and R together work on a job, in what ratio should they share the earnings?
Answer (a) & explanation
They should share in the ratio 3 : 1 : 1 (a). Step 1: P works three times as fast as Q. Take Q's rate as 1, so P's rate is 3. Step 2: P and Q together work four times as fast as R. P + Q = 3 + 1 = 4, so 4 = 4 × R, which gives R = 1. Step 3: earnings are shared by the amount of work done, which follows the rates. So P : Q : R = 3 : 1 : 1. Option (d), 3 : 1 : 4, treats R as 4. Options (b) and (c) do not fit.
Tip: when people work for the same time, share pay in the ratio of their speeds. Set the slowest person's speed as 1 to keep numbers simple.
Answer as per the official UPSC answer key.
Which principle among the following was added to the Directive Principles of State Policy by the 42nd Amendment to the Constitution?
Answer (b) & explanation
Workers' participation in management was added by the 42nd Amendment (b). The 42nd Amendment (1976) added Article 43A (workers in management), Article 39A (equal justice and free legal aid) and Article 48A (protecting the environment and wildlife). It also amended Article 39(f) on healthy child development. The other options were already in the original Constitution: equal pay for men and women (a) is Article 39(d); the right to work, education and public assistance (c) is Article 41; and a living wage and humane working conditions (d) are Article 43.
Later amendments added more principles: the 44th added Article 38(2) on reducing inequalities, the 86th changed Article 45 on early childhood care, and the 97th added Article 43B on cooperatives.
(a) sounds modern, but equal pay was there from 1950.
Answer as per the official UPSC answer key.
What is the purpose of setting up of Small Finance Banks (SFBs) in India ?
- 1. To supply credit to small business units
- 2. To supply credit to small and marginal farmers
- 3. To encourage young entrepreneurs to set up business particularly in rural areas.
Select the correct answer using the code given below :
Answer (a) & explanation
Statements 1 and 2 are correct (a). The RBI's 2014 guidelines say Small Finance Banks exist for financial inclusion. They offer savings services and give credit to small business units (1), small and marginal farmers (2), micro and small industries and the unorganised sector. Statement 3 is wrong because encouraging young entrepreneurs in rural areas is not a stated purpose. At least 75% of their loans must go to the priority sector, and at least half their loans must be up to ₹25 lakh.
Many SFBs, such as AU, Ujjivan and Equitas, began as NBFCs or microfinance lenders. Notice how they differ from Payments Banks: payments banks take deposits (up to ₹2 lakh) but cannot lend, and AU later applied to become a universal bank.
statement 3 sounds like a good aim. UPSC tests the RBI's stated objectives, word for word.
Answer as per the official UPSC answer key.
Organic Light Emitting Diodes (OLEDs) are used to create digital display in many devices. What are the advantages of OLED displays over Liquid Crystal displays ?
- 1. OLED displays can be fabricated on flexible plastic substrates.
- 2. Roll-up displays embedded in clothing can be made using OLEDs.
- 3. Transparent displays are possible using OLEDs.
Select the correct answer using the code given below :
Answer (c) & explanation
All three are correct (c). In an OLED display, each pixel is made of organic compounds that give off their own light, so it needs no backlight. The layers are very thin and can be laid on flexible plastic (1). This makes possible foldable and roll-up screens, including ones built into clothing (2), as well as transparent displays (3). Backlit LCDs cannot do any of these easily. OLEDs also show true blacks and high contrast, because a pixel can switch off fully, and they use less power for dark images.
Their drawbacks are burn-in and a shorter life for blue pixels. Notice the next steps: MicroLED and QD-OLED. Foldable phones and rollable TVs now use flexible OLEDs.
Answer as per the official UPSC answer key.
Read the passage
What climate change will undeniably do is cause or amplify events that hasten the reduction of resources. Competition over these diminishing resources would ensue in the form of political or even violent conflict. Resource-based conflicts have rarely been overt and are thus difficult to isolate. Instead they take on veneers that appear more politically palatable. Conflicts over resources like water are often cloaked in the guise of identity or ideology.
What does the above passage imply?
Answer (c) & explanation
The passage implies that environmental issues add to resource stress and political conflict (c). Step 1: it says climate change speeds up "the reduction of resources", and competition for them can turn into "political or even violent conflict". That is option (c). Step 2: option (a) says such conflicts are always political. The word "always" goes too far. Step 3: options (b) and (d) say there are no solutions or that conflicts cannot be resolved. The passage never discusses solutions at all.
Tip: when a passage describes a chain, here climate to scarcity to conflict, the right answer usually restates that chain. Reject options with "always", "no" or "cannot" unless the passage says so.
Answer as per the official UPSC answer key.
A clock strikes once at 1 o'clock, twice at 2 o'clock and thrice at 3 o'clock, and so on. If it takes 12 seconds to strike at 5 o'clock, what is the time taken by it to strike at 10 o'clock?
Answer (b) & explanation
The official answer is 24 seconds (b). Step 1: the official key treats the time as shared per strike. Five strikes take 12 seconds. Step 2: ten strikes are twice five strikes, so the time doubles: 12 × 2 = 24 seconds. Step 3: strictly, a clock's time runs between strikes. Five strikes have 4 gaps, so each gap is 3 seconds, and ten strikes have 9 gaps, which would give 27 seconds. Since 27 is not an option, UPSC's key follows the simple per-strike method. Options (a), (c) and (d) do not fit either method.
Tip: if the gap method gives no matching option, fall back on simple proportion, as UPSC did here.
Counting the gaps between strikes (4 gaps take 12 s, so 9 gaps take 27 s) gives 27 s, which is not an option; the official answer is (b).
Answer as per the official UPSC answer key.