UPSC Prelims Science and Technology Questions 2025, Check Last Year's Trends

UPSC Prelims Science and Technology Questions: The UPSC Civil Services Preliminary exam was conducted on May 25, 2025. Science and Technology is a vital section in GS Paper, divided into Physics, Chemistry, and Biology, and many sub-themes, such as nanotechnology, biotechnology, space technology, genetic engineering, DNA, RNA, and everyday science.

In UPSC Prelims 2025, the Science and Technology section included 13 questions covering an overall weight of 10-15%. The questions were based on the latest technological advancements, ISRO missions, defence innovations, and fundamental scientific concepts.

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UPSC Prelims Science and Technology No of Questions & Analysis

The UPSC Prelims General Studies paper, held on May 25, 2025, covers a significant weightage from the Science and Technology section, reflecting that it is a crucial part and aspirants can't avoid it to secure the desired score.

The section consisted of a total of 13 questions across a wide variety of topics like ISRO Missions, Defence Technology, Information Technology, Nanotechnology, and daily life science applications.

Based on the UPSC Prelims Exam Analysis 2025 by PW, this section was easy to moderate with a diverse set of questions. Candidates can find the list of questions asked in UPSC Prelims 2025 from the Science & Technology section with their answers below.

Also, Read:

• UPSC Prelims Polity Questions
• UPSC Prelims Economy Questions
• UPSC Prelims IR Questions

UPSC Prelims Science and Technology Questions with Answers

Practicing these questions will aid your preparation for the upcoming exams and help to identify the high-yield topics. We have compiled a comprehensive list of questions with their answers in this section:

1. Consider the following types of vehicles:  

I. Full battery electric vehicles   

II. Hydrogen fuel cell vehicles   

III. Fuel cell-electric hybrid vehicles   

How many of the above are considered as alternative powertrain vehicles?   

(a) Only one   

(b) Only two   

(c) All the three   

(d) None   

2. With reference to Unmanned Aerial Vehicles (UAVs), consider the following statements:  

I. All types of UAVs can do vertical landing.   

II. All types of UAVs can do automated hovering.   

III.All types of UAVs can use battery only as a source of power supply.   

How many of the statements given above are correct?  

(a) Only one    

(b) Only two  

(c) All the three   

(d) None 

3. In the context of electric vehicle batteries, consider the following elements:  

I. Cobalt  

II. Graphite  

III. Lithium   

IV. Nickel

How many of the above usually make up battery cathodes?   

(a) Only one   

(b) Only two   

(c) Only three   

(d) All the four 

4. What is the common characteristic of the chemical substances generally known as CL-20, HMX and LLM-105, which are sometimes talked about in media?

(a) These are alternatives to hydrofluorocarbon refrigerants   

(b) These are explosives in military weapons   

(c) These are high-energy fuels for cruise missiles   

(d) These are fuels for rocket propulsion 

 5. Consider the following statements:  

I. It is expected that Majorana 1 chip will enable quantum computing.  

II. Majorana 1 chip has been introduced by Amazon Web Services (AWS).  

III. Deep learning is a subset of machine learning.   

Which of the statements given above are correct?   

(a) I and II only   

(b) II and III only   

(c) I and III only   

(d) I, II and III 

6. With reference to monoclonal antibodies, often mentioned in news, consider the following statements:

I. They are man-made proteins.

II. They stimulate immunological function due to their ability to bind to specific antigens.

III. They are used in treating viral infections like that of Nipah virus.

Which of the statements given above are correct?

(a) I and II only

(b) II and III only

(c) I and III only

(d) I, II and III

7. Consider the following statements:  

I. No virus can survive in ocean water.  

II. No virus can infect bacteria.  

III. No virus can change the cellular transcriptional activity in host cells.  

How many of the statements given above are correct?   

(a) Only one   

(b) Only two   

(c) All the three   

(d) None 

8. Consider the following statements:  

Statement I: Studies indicate that carbon dioxide emissions from cement industry account for more than 5% of global carbon emissions.  

Statement II: Silica-bearing clay is mixed with limestone while manufacturing cement.  

Statement III: Limestone is converted into lime during clinker production for cement manufacturing. 

Which one of the following is correct in respect of the above statements?   

(a) Both Statement II and Statement III are correct and both of them explain Statement I   

(b) Both Statement II and Statement III are correct but only one of them explains Statement I   

(c) Only one of the Statements II and Statement  III is correct and that explain statement t I   

(d) Neither Statement II nor Statement III is correct 

9. GPS-Aided Geo Augmented Navigation (GAGAN) uses a system of ground stations to provide necessary augmentation. Which of the following statements is/are correct in respect of GAGAN? 

I. It is designed to provide additional accuracy and integrity.  

II. It will allow more uniform and high quality air traffic management.  

III. It will provide benefits only in aviation but not in other modes of transportation.  

Select the correct answer using the code given below.  

(a) I, II and III  

(b) I only  

(c) II and III only  

(d) I and II only  

10. Consider the following statements regarding AI Action Summit held in Grand Palais, Paris in February 2025:

I. Co-chaired with India, the event builds on the advances made at the Bletchley Park Summit held in 2023 and the Seoul Summit held in 2024.  

II. Along with other countries, the US and UK also signed the declaration on inclusive and sustainable AI.  

Which of the statements given above is/are correct?  

(a) I only  

(b) II only  

(c) Both I and I   

(d) Neither I nor II  

11. Consider the following statements:

Statement I: Some rare earth elements are used in the manufacture of flat television screens and computer monitors.   

Statement II:  Some rare earth elements have phosphorescent properties.   

Which one of the following is correct?   

(a) Both are correct and II explains I   

(b) Both are correct but II does not explain I   

(c) Only I is correct   

(d) Only II is correct   

12. Consider the following space missions: 

I. Axiom-4   

II. SpaDeX   

III. Gaganyaan   

How many of the space missions given above encourage and support microgravity research?    

(a) Only one   

(b) Only two   

(c) All three 

(d) None 

13. With reference to India’s defence, consider the following pairs:

How many of the pairs are correctly matched?

(a) Only one   

(b) Only two   

(c) All three   

(d) None

Also, Check: UPSC Prelims Topic-wise Questions

UPSC Prelims Science and Technology PYQs with Answers

UPSC Prelims Science and Technology questions assess candidates' understanding of recent scientific advancements and their applications. This section often includes topics like biotechnology, space technology, information technology, and health science. 

To prepare effectively, it's crucial to review previous years' questions and prioritize high-weightage topics. The direct link to UPSC Prelims Science and Technology questions with answers is provided in the table below:

UPSC Prelims Science and Technology Questions 2024

Question 1:
Which one of the following words/phrases is most appropriately used to denote “an interoperable network of 3D virtual worlds that can be accessed simultaneously by millions of users, who can exert property rights over virtual items”?

(a) Big data analytics
(b) Cryptography
(c) Metaverse
(d) Virtual matrix

Question 2:
With reference to radioisotope thermoelectric generators (RTGs), consider the following statements:

1. RTGs are miniature fission reactors.
2. RTGs are used for powering the onboard systems of spacecraft.
3. RTGs can use Plutonium-238, which is a by-product of weapons developments.

Which of the statements given above are correct?

(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2, and 3

Question 3:
Consider the following statements:

Statement I: Giant stars live much longer than dwarf stars.
Statement II: Compared to dwarf stars, giant stars have a greater rate of nuclear reactions.

Which one of the following is correct in respect of the above statements?

(a) Both Statement-I and Statement-II are correct and Statement-II explains Statement-I
(b) Both Statement-I and Statement-II are correct, but Statement-II does not explain Statement-I
(c) Statement I is correct, but Statement II is incorrect
(d) Statement I is incorrect, but Statement II is correct

Question 4:
Which one of the following is synthesised in the human body that dilates blood vessels and increases blood flow?

(a) Nitric oxide
(b) Nitrous oxide
(c) Nitrogen dioxide
(d) Nitrogen pentoxide

Question 5:
Consider the following activities:

1. Identification of narcotics on passengers at airports or in aircraft
2. Monitoring of precipitation
3. Tracking the migration of animals

In how many of the above activities can radars be used?

(a) Only one
(b) Only two
(c) All three
(d) None

Question 6:
Consider the following aircraft:

1. Rafael
2. MiG-29
3. Tejas MK-1

How many of the above are considered fifth-generation fighter aircraft?

(a) Only one
(b) Only two
(c) All three
(d) None

Question 7:
In which of the following are hydrogels used?

1. Controlled drug delivery in patients
2. Mobile air-conditioning systems
3. Preparation of industrial lubricants

Select the correct answer using the code given below:

(a) 1 only
(b) 1 and 2 only
(c) 2 and 3 only
(d) 1, 2, and 3

Question 8:
Which one of the following is the exhaust pipe emission from Fuel Cell Electric Vehicles, powered by hydrogen?

(a) Hydrogen peroxide
(b) Hydronium
(c) Oxygen
(d) Water vapour

Question 9:
Recently, the term “pumped-storage hydropower” is actually and appropriately discussed in the context of which one of the following?

(a) Irrigation of terraced crop fields
(b) Lift irrigation of cereal crops
(c) Long duration energy storage
(d) Rainwater harvesting system

Question 10:
“Membrane Bioreactors” are often discussed in the context of:

(a) Assisted reproductive technologies
(b) Drug delivery nanotechnologies
(c) Vaccine production technologies
(d) Wastewater treatment technologies

UPSC Prelims Science and Technology Questions 2023

Question 1: Consider the following statements:

1. Some microorganisms can grow in environments with temperatures above the boiling point of water.
2. Some microorganisms can grow in environments with temperatures below the freezing point of water.
3. Some microorganisms can grow in a highly acidic environment with a pH below 3.

How many of the above statements are correct?
(a) Only one
(b) Only two
(c) All three
(d) None

Question 2: With reference to green hydrogen, consider the following statements:

1. It can be used directly as a fuel for internal combustion.
2. It can be blended with natural gas and used as fuel for heat or power generation.
3. It can be used in a hydrogen fuel cell to run vehicles.

How many of the above statements are correct?
(a) Only one
(b) Only two
(c) All three
(d) None

Question 3: ‘Wolbachia method’ is sometimes talked about with reference to which one of the following?
(a) Controlling the viral diseases spread by mosquitoes
(b) Converting crop residues into packing material
(c) Producing biodegradable plastics
(d) Producing biochar from thermo-chemical conversion of biomass

Question 4: ‘Aerial metagenomics’ best refers to which one of the following situations?
(a) Collecting DNA samples from air in a habitat at one go
(b) Understanding the genetic makeup of avian species of a habitat
(c) Using airborne devices to collect blood samples from moving animals
(d) Sending drones to inaccessible areas to collect plant and animal samples from land surfaces and water bodies

Question 5: ‘Microsatellite DNA’ is used in the case of which one of the following?
(a) Studying the evolutionary relationships among various species of fauna
(b) Stimulating ‘stem cells’ to transform into diverse functional tissues
(c) Promoting clonal propagation of horticultural plants
(d) Assessing the efficacy of drugs by conducting a series of drug trials in a population

Question 6: Consider the following actions:

1. Detection of car crash/collision, which results in the deployment of airbags almost instantaneously.
2. Detection of accidental free fall of a laptop towards the ground, which results in the immediate turning off of the hard drive.
3. Detection of the tilt of a smartphone, which results in the rotation of the display between portrait and landscape mode.

How many of the above actions is the function of the accelerometer required?
(a) Only one
(b) Only two
(c) All three
(d) None

Question 7: With reference to the role of biofilters in Recirculating Aquaculture Systems, consider the following statements:

1. Biofilters provide waste treatment by removing uneaten fish feed.
2. Biofilters convert ammonia present in fish waste to nitrate.
3. Biofilters increase phosphorus as a nutrient for fish in water.

How many of the statements given above are correct?
(a) Only one
(b) Only two
(c) All three
(d) None

How many of the above pairs are correctly matched?
(a) Only one
(b) Only two
(c) All three
(d) None

Question 9: Consider the following statements:

1. Ballistic missiles are jet-propelled at subsonic speeds throughout their flights, while cruise missiles are rocket-powered only in the initial phase of flight.
2. Agni-V is a medium-range supersonic cruise missile, while BrahMos is a solid-fueled intercontinental ballistic missile.

Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2

Previous Year Trends of UPSC Prelims Science and Technology Questions

Section-wise UPSC Prelims Science and Technology Questions

1. Assess the age of a plant or animal.
2. Distinguish among species that look alike.
3. Identify undesirable animal or plant materials in processed foods.

Which of the statements given above is/are correct? (2022)
(a) 1 only
(b) 3 only
(c) 1 and 2
(d) 2 and 3
Ans: (d) 2 and 3

Microorganism: Consider the following statements in respect of probiotics:

1. Probiotics are made of both bacteria and yeast.
2. The organisms in probiotics are found in food we ingest but they do not naturally occur in our gut.
3. Probiotics help in the digestion of milk sugars.

Which of the statements given above is/are correct? (2022)
(a) 1 only
(b) 2 only
(c) 1 and 3
(d) 2 and 3
Ans: (c) 1 and 3

Cell Biology: Which of the following statements are correct regarding the general difference between plant and animal cells? (2022)

1. Plant cells have cellulose cell walls whilst animal cells do not.
2. Plant cells do not have plasma membranes unlike animal cells which do.
3. Mature plant cell has one large vacuole whilst an animal cell has many small vacuoles.

Select the correct answer using the code given below:
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Ans: (c) 1 and 3 only

Health and Disease: In the context of hereditary diseases, consider the following statements:

1. Passing on mitochondrial diseases from parent to child can be prevented by mitochondrial replacement therapy either before or after in vitro fertilization of the egg.
2. A child inherits mitochondrial diseases entirely from mother and not from father.

Which of the statements given above is/are correct? (2021)
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Ans: (c) Both 1 and 2

Physics: Communication Technology: With reference to Visible Light Communication (VLC) technology, which of the following statements are correct? (2020)

1. VLC uses electromagnetic spectrum wavelengths 375 to 780 nm.
2. VLC is known as long-range optical wireless.
3. VLC can transmit large amounts of data faster than Bluetooth.
4. VLC has no electromagnetic interference.

Select the correct answer using the code given below:
(a) 1, 2, and 3 only
(b) 1, 2, and 4 only
(c) 1, 3, and 4 only
(d) 2, 3, and 4 only
Ans: (c) 1, 3 and 4 only

The experiment will employ a trio of spacecraft flying in formation in the shape of an equilateral triangle that has sides one million kilometers long, with lasers shining between the craft. The experiment in question refers to:

(a) Voyager 2
(b) New Horizons
(c) LISA Pathfinder
(d) Evolved LISA

Answer: (d) Evolved LISA

1. SaaS buyers can customize the user interface and can change data fields.
2. SaaS users can access their data through their mobile devices.
3. Outlook, Hotmail and Yahoo Mail are form of SaaS

 Which one of the following is the context in which the term “qubit” is mentioned? (2022)

  (a) Cloud Services 

 (b) Quantum Computing

  (c) Visible Light Communication Technologies

  (d) Wireless Communication Technologies

  Ans: b

Nanotechnology

 Consider the following statements:

1. Other than those made by humans, nanoparticles do not exist in nature.
2. Nanoparticles of some metallic oxides are used in the manufacture of some cosmetics.
3. Nanoparticles of some commercial products which enter the environment are unsafe for

 Units and Measurement

  Which one of the following is a reason why astronomical distances are measured in light-years? (2021)

  (a) Distances among stellar bodies do not change.

  (b) Gravity of stellar bodies does not change.

  (c) Light always travels in a straight line.

  (d) Speed of light is always the same.

  Ans: d

 Everyday Science

With reference to street lighting, how do sodium lamps differ from LED lamps?

1. Sodium lamps produce light in 360 degrees but it is not so in the case of LED lamps.
2. As street lights, sodium lamps have a longer lifespan than LED lamps.
3. The spectrum of visible light from sodium lamps is almost monochromatic while LED lamps offer significant colour advantages in street lighting.

  Chemistry: Chemical Compounds

  Consider the following statements:

1. According to the Indian Patents Act, a biological process to create a seed can be patented in
2. In India, there is no Intellectual Property Appellate
3. Plant varieties are not eligible to be patented in