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UPSC Prelims 2026 · GS Paper I: Which of the following statements regarding the features of blockchain technology are correct ?1.…

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UPSC Prelims 2026 · GS Paper I

Which of the following statements regarding the features of blockchain technology are correct ?

  • 1. Records stored in the database may be made visible to relevant stakeholders without risk of alteration.
  • 2. Copies of the entire database are stored on multiple computers on a network, syncing within seconds.
  • 3. Consortium blockchain is a blend of public and private blockchains allowing selective data access.
  • 4. Mathematical algorithms make it impossible to change or delete any data once recorded and accepted.

Select the answer using the code given below :

Answer (c) & explanation

Statements 1, 2 and 4 are correct (c). A blockchain is a shared record of transactions copied across many computers. Statement 1 is right: records can be shown to stakeholders without risk of alteration. Statement 2 is right: copies of the whole ledger sit on many nodes and sync quickly. Statement 4 is right: cryptographic hashing links each block to the last, so accepted data cannot be changed or deleted. Statement 3 is wrong: a blend of public and private is a hybrid blockchain; a consortium blockchain is run by a group of organisations. So options (a), (b) and (d) fail.

Notice uses in India: land records, supply chains, and the RBI's e-rupee pilots. Bitcoin (2009) was the first public blockchain.

Trap

Consortium and hybrid both sound like a mix. Consortium means many owners; hybrid means a mix of public and private.

Answer as per the official UPSC answer key.

Same theme in UPSC Mains

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UPSC Prelims 2026 · GS Paper I

Which of the following statements with regard to Black Boxes used in modern aircrafts is/are correct ?

  • 1. They carry a beacon emitting red light pulses to facilitate underwater detection.
  • 2. They record both the cockpit voice and flight data.
  • 3. Their memory units are made using either stainless steel or titanium.

Select the answer using the code given below :

Answer (b) & explanation

Statements 2 and 3 are correct (b). Statement 2 is right: the "black box" is really two orange recorders, the cockpit voice recorder and the flight data recorder. Statement 3 is right: their crash-survivable memory sits in stainless steel or titanium shells. Statement 1 is wrong: under water, the locator beacon sends out ultrasonic pulses, about 37.5 kHz, not red light. So options (a), (c) and (d) fail.

Notice why they are orange: to be easy to spot in wreckage. The beacon works for about 30 to 90 days. Black boxes were key in probing the Air India Ahmedabad crash (June 2025); India's AAIB read its data at a new lab in Delhi. Newer rules call for 25-hour voice recording.

Answer as per the official UPSC answer key.

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UPSC Prelims 2026 · GS Paper I

Consider the following statements with regard to involvement of private entities in India’s space programme :

  • 1. The Indian National Space Promotion and Authorisation Centre (IN-SPACe) is an autonomous agency formed to facilitate participation of private entities.
  • 2. Agnikul Cosmos launched the world’s first flight using 3D-printed rocket engine.
  • 3. Skyroot Aerospace has developed liquid fuel for GSLV.

Which of the statements given above is/are correct ?

Answer (c) & explanation

Statements 1 and 2 are correct (c). Statement 1 is right: IN-SPACe (2020) is the single-window, autonomous body under the Department of Space that authorises private space activity. Statement 2 is right: Agnikul's Agnibaan SOrTeD (May 2024) flew on the world's first single-piece 3D-printed semi-cryogenic engine. Statement 3 is wrong: Skyroot builds its own Vikram rockets; it does not make fuel for ISRO's GSLV. So options (a), (b) and (d) fail.

Notice Skyroot's milestone: Vikram-S (2022) was India's first privately built rocket to reach space. The Indian Space Policy, 2023 opened all space activities to private firms, and 100% FDI is allowed in parts of the sector. NSIL is ISRO's commercial arm.

Answer as per the official UPSC answer key.

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UPSC Prelims 2026 · GS Paper I

Which of the following statements with regard to drone swarms is/are correct ?

  • 1. They use Terahertz band of frequency to communicate with the command centre.
  • 2. Individual drones in the swarm can communicate with other drones in the swarm.
  • 3. GPS Spoofing is a commonly used technique to counter drone swarm attack.

Select the answer using the code given below :

Answer (b) & explanation

Statements 2 and 3 are correct (b). Statement 2 is right: in a swarm, the drones talk to each other and share tasks, so the group keeps working even if some are lost. Statement 3 is right: defenders often jam or spoof GPS to send them off course. Statement 1 is wrong: swarms usually use ordinary radio bands; terahertz links are still experimental and short-range. So options (a), (c) and (d) fail.

Notice other counters: laser weapons, like DRDO's directed-energy systems, anti-drone guns and net systems. India showed a 75-drone swarm at the 2021 Army Day parade. Drone wars in Ukraine and during Operation Sindoor (2025) showed how cheap drones can overwhelm costly defences.

Answer as per the official UPSC answer key.

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UPSC Prelims 2026 · GS Paper I

Which of the following statements with regard to GenomeIndia Project is/are correct ?

  • 1. It is a part of the Human Genome Project.
  • 2. The project is funded by the Department of Biotechnology (DBT), Government of India.
  • 3. Its primary aim is to build a catalogue of genetic diversity of the Indian population.

Select the answer using the code given below :

Answer (b) & explanation

Statements 2 and 3 are correct (b). Statement 2 is right: GenomeIndia (2020) is funded by the Department of Biotechnology. Statement 3 is right: it sequenced 10,000 genomes from many Indian communities to build a catalogue of the country's genetic variation, and the data was released in 2025. Statement 1 is wrong: the international Human Genome Project was a separate effort that ended in 2003. So options (a), (c) and (d) fail.

Notice the uses: finding gene variants behind diseases common in India, such as sickle cell and thalassaemia, and building personalised medicine. The data is stored at the Indian Biological Data Centre in Faridabad. A larger follow-up aims to sequence one million genomes.

Answer as per the official UPSC answer key.

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