Science & Technology Mixed Quiz: Set 28

The correct answer is A, Vitalik Buterin. Ethereum was described by Vitalik Buterin in a white paper of 2013 and the network went live in 2015. Its contribution was to add a general purpose computing layer, the Ethereum Virtual Machine, on top of a blockchain, so that programs called smart contracts could be stored on the chain and run by themselves; contracts are written in languages such as Solidity and the computation is paid for in a fee called gas. Its token is ether. Option B is wrong because Satoshi Nakamoto is the name on the bitcoin paper of 2008, and bitcoin has no general contract layer. Option C is wrong because Charlie Lee created Litecoin, an early alternative coin based on the bitcoin code. Option D is wrong because Hal Finney was an early bitcoin developer who received one of the first bitcoin transactions, not the founder of Ethereum.

The correct answer is B, Ahmedabad. The Indian National Space Promotion and Authorisation Centre, IN-SPACe, is an autonomous body under the Department of Space with its headquarters at Ahmedabad in Gujarat, the city where India's space programme itself began at the Physical Research Laboratory founded by Vikram Sarabhai. IN-SPACe authorises and supervises the space activities of private companies and lets them use ISRO's facilities. Option A is wrong because Bengaluru is the headquarters of ISRO itself, of Antrix Corporation and of NewSpace India Limited, which is why it is the common wrong choice here. Option C is wrong because Hyderabad is the home of the launch-vehicle start-up Skyroot Aerospace and of ISRO's Nuclear Fuel Complex neighbours, not of IN-SPACe. Option D is wrong because Thiruvananthapuram hosts the Vikram Sarabhai Space Centre, where launch vehicles are developed.

The correct answer is A, Prarambh. Skyroot Aerospace named the maiden flight of Vikram-S Mission Prarambh, a Sanskrit word meaning beginning, because it was the first flight by a private Indian rocket. The vehicle rose on a sub-orbital path from a launch pad at the Satish Dhawan Space Centre and carried three small customer payloads. Option B is wrong because SOrTeD, short for Sub-Orbital Technology Demonstrator, is the name of the Agnikul Cosmos flight of Agnibaan in 2024, a different company and a different year. Option C is wrong because Pragyan is the name of the rover carried by India's Chandrayaan missions to the Moon. Option D is wrong because Prathama is not the name of any Indian space mission, and is included only as a plausible-sounding distractor.

The correct answer is B, Satoshi Nakamoto. The paper titled Bitcoin: A Peer-to-Peer Electronic Cash System was circulated in 2008 under the name Satoshi Nakamoto, a pseudonym whose owner has never been established, and it set out how a chain of hashed blocks and proof of work could prevent double spending without any trusted third party. The first block of the chain was mined in January 2009. Option A is wrong because Vitalik Buterin proposed Ethereum in 2013, five years later, and Ethereum is a different network built for smart contracts. Option C is wrong because Nick Szabo coined the term smart contract in the 1990s and designed an earlier scheme called bit gold, but did not write this paper. Option D is wrong because Ralph Merkle devised the Merkle tree, the hashing structure that bitcoin uses inside a block, decades before bitcoin existed.

The correct answer is B, the Merkle root. The transactions in a block are hashed in pairs, the resulting hashes are hashed in pairs again, and the process repeats until a single hash remains; that hash is the Merkle root, named after Ralph Merkle, and it is stored in the block header. Its value is that a change in any one transaction changes the root, so tampering is detected at once, and a light client can prove that one transaction belongs to a block without downloading the whole block. Option A is wrong because the nonce is the number miners vary to make the block hash meet the difficulty target. Option C is wrong because the genesis block is simply the first block of a chain, which has no predecessor. Option D is wrong because a private key is the secret a user keeps to sign transactions from an address.

The correct answer is C, agricultural and allied produce. Agmark is a grade mark given under the Agricultural Produce (Grading and Marking) Act, 1937 to produce such as edible oils, ghee, butter, honey, spices, pulses, wheat flour, besan and eggs, and it is administered by the Directorate of Marketing and Inspection under the Ministry of Agriculture and Farmers’ Welfare. The name is a contraction of agricultural marketing. Option A is wrong because electrical appliances carry the ISI mark and the BEE star rating. Option B is wrong because gold and silver carry the hallmark of the Bureau of Indian Standards, which certifies purity and not grade. Option D is wrong because handloom cloth carries the Handloom Mark launched in 2006, while pure silk carries the Silk Mark of the Silk Mark Organisation of India.

The correct answer is B. Agnibaan SOrTeD, flown by Agnikul Cosmos of Chennai in 2024, carried the Agnilet engine, a semi-cryogenic engine printed as a single piece, and it lifted off from a launch pad the company had built for itself at the Satish Dhawan Space Centre. Both the printed engine and the private launch pad were firsts for India. Option A is wrong because solid propellant has been used in Indian rockets since the Rohini sounding rockets and the SLV-3; Agnibaan in fact uses a liquid and gaseous combination. Option C is wrong because SOrTeD was a sub-orbital technology demonstration and did not attempt orbit; the first Indian rocket to reach orbit was the SLV-3 in 1980. Option D is wrong because no Indian booster has yet landed back for reuse, although ISRO has tested landing technologies separately.

The correct answer is B, the Kodaikanal Solar Observatory in the Palani hills of Tamil Nadu, set up in 1899 when solar work was moved from the old Madras Observatory to a hill station with clearer air. It is now part of the Indian Institute of Astrophysics, and its digitised archive of daily photographs of the solar disc, sunspots and the chromosphere is among the longest continuous records of the Sun anywhere, which makes it valuable for the study of long solar cycles. A is a night-time optical observatory for stars and galaxies. C watches the Sun but at radio frequencies and was set up much later. D is an optical site of the twenty-first century with no solar programme of this kind. Its sunspot drawings and spectroheliograms are now used to reconstruct the solar activity of the past hundred years.

The correct answer is B, distributed ledger technology. A blockchain is a ledger whose identical copies are held by many nodes, with new entries grouped into blocks, each linked to the previous one by its hash, and added only when the network agrees by a consensus rule. Distributed ledger technology is the wider family; a blockchain is the form in which entries are batched into hash-linked blocks, while other designs in the family do not use blocks at all. Option A is wrong because a relational database is held and controlled by one administrator who can edit or delete rows, which is the opposite of an append-only shared record. Option C is wrong because cloud storage merely keeps files on someone else's servers, with no consensus or tamper-evidence. Option D is wrong because an operating system manages the hardware and software of a single machine.

The correct answer is B, STL. An STL file describes the outer surface of a three-dimensional object as a mesh of triangles and carries no colour, material or texture information. A design made in computer-aided design software is exported as STL, and a slicing program then cuts it into horizontal layers and writes the machine instructions, usually G-code. Option A is wrong because JPEG is a compressed format for flat photographic images and has no depth information at all. Option C is wrong because MPEG is a family of standards for compressing video and audio. Option D is wrong because PDF is a format for fixed-layout documents meant for reading and printing on paper, not for driving a printer that builds in three dimensions. Candidates should remember that the STL file stores geometry alone, which is why colour printing needs newer formats built on top of it.

The correct answer is C, 1992. Antrix Corporation Limited was set up in 1992 at Bengaluru as a wholly government-owned company under the Department of Space, to market the products and services of the Indian space programme abroad, including launch services, satellite capacity and remote sensing data. Option A is wrong because 1969 is the year ISRO itself was formed, on the fifteenth of August. Option B is wrong because 1972 is the year the Space Commission and the Department of Space were created, which brought the programme under a department reporting to the Prime Minister. Option D is wrong because no space body of note was created in 2003; the next commercial body after Antrix was NewSpace India Limited in 2019, and the examiner's trap is to mix up the two companies and their years.

The correct answer is A, a light combat helicopter. Prachand is the Light Combat Helicopter developed and built by Hindustan Aeronautics Limited, designed to operate from high-altitude bases, which makes it suited to the Siachen and Ladakh sectors where few attack helicopters can carry a useful load. Option B, a basic trainer, is the role of the HAL HTT-40, while the HJT-16 Kiran served as an intermediate jet trainer. Option C, an unmanned aerial vehicle, describes Nishant and the TAPAS or Rustom series of Indian designs. Option D, a maritime patrol aircraft, describes the P-8I flown by the Navy for surveillance and anti-submarine work. HAL's other helicopters worth remembering are Dhruv, the advanced light helicopter, and Rudra, its armed version, while the Apache attack helicopter and the Chinook heavy-lift helicopter are imported from Boeing of the United States.

The correct answer is C, thirty per cent. The Finance Act of 2022 inserted a definition of the virtual digital asset into the Income Tax Act and taxed income from the transfer of such an asset at a flat thirty per cent, plus the applicable surcharge and cess. No deduction is allowed except the cost of acquisition, no expenditure or allowance may be set off, and a loss from one such asset cannot be set off against gains from another or carried forward. Option A is wrong because ten per cent is the long term capital gains rate applicable to certain listed securities, not to these assets. Option B is wrong because twenty per cent applies to long term capital gains with indexation in other contexts. Option D is wrong because forty per cent is a corporate rate for certain foreign companies and has nothing to do with these assets.

The correct answer is B, the National Payments Corporation of India. The NPCI, set up in 2008 under the Payment and Settlement Systems Act of 2007 by the Reserve Bank and the Indian Banks' Association, launched UPI in 2016; it also runs RuPay, IMPS, the Aadhaar Enabled Payment System, NACH and FASTag. Option A is wrong but is the commonest mistake, because the Reserve Bank promoted the NPCI and regulates payment systems, yet UPI is an NPCI product. Option C is wrong; the State Bank of India is one of the banks that participate in UPI, not its owner. Option D is wrong because the Ministry of Electronics and Information Technology runs DigiLocker and the Digital India programme, not the payments layer. UPI forms the payments layer of what is called India Stack.

The correct answer is C, IN-SPACe. Under the reforms of 2020 and the Indian Space Policy of 2023, the Indian National Space Promotion and Authorisation Centre is the single-window autonomous body that authorises, promotes, hand-holds and supervises the space activities of non-government entities, and that permits them to use the facilities of the Department of Space. Option A is wrong because ISRO is the research and development agency; under the new division of labour it is to concentrate on advanced missions and transfer proven technology to industry rather than regulate it. Option B is wrong because NSIL is a commercial company, a buyer and seller in the market, not a regulator. Option D is wrong because Antrix is the older commercial arm and also has no regulatory role; mixing up the regulator with the two commercial companies is the usual mistake.

The correct answer is B, the interpretation of the genetic code. Khorana shared the Nobel Prize in Physiology or Medicine in 1968 with Robert Holley and Marshall Nirenberg for showing how the sequence of nucleotides in nucleic acids specifies the amino acids of a protein; he later synthesised the first artificial gene, a landmark in molecular biology. He was born at Raipur in undivided Punjab and later became a citizen of the United States. Option A is wrong; alkaloid chemistry is associated with Asima Chatterjee, who worked on anti-epileptic and anti-malarial compounds. Option C is wrong; the structure and function of the ribosome brought Venkatraman Ramakrishnan a share of the Nobel Prize in Chemistry in 2009, four decades later. Option D is wrong; plant physiology is the field of Jagadish Chandra Bose, who built the crescograph to measure growth and showed that plants respond to stimuli.

The correct answer is A, one per cent. From July 2022 a person paying any consideration for the transfer of a virtual digital asset must deduct tax at source at one per cent of that consideration, a provision introduced by the Finance Act of 2022 so that the tax department can see the volume and the parties in this market. Small transfers below the prescribed limits for specified persons are exempt, and the deduction applies whether the consideration is in money or in kind. Option B is wrong because two per cent is the rate for certain cash withdrawals and contract payments, not for these assets. Option C is wrong because five per cent appears in other withholding provisions such as some interest payments to non-residents. Option D is wrong because ten per cent is a common rate for professional fees and dividends; using it here is the usual error in this question.

The correct answer is C, 74 per cent. The amendment approved by the Union Cabinet in February 2024 divides space activities into three groups with different automatic-route ceilings. Satellite manufacturing and operation, satellite data products and the ground and user segment are open to foreign investment up to 74 per cent through the automatic route, and investment beyond that level requires government approval. Option A is wrong because 49 per cent is the automatic-route ceiling for launch vehicles, their systems or sub-systems, and spaceports. Option B is wrong because 51 per cent is not a ceiling used anywhere in the space policy, although it appears in other sectors. Option D is wrong because 100 per cent through the automatic route applies only to the manufacture of components, systems and sub-systems for satellites and for the ground and user segment.

The correct answer is B, a central bank digital currency. The digital rupee, written as e-rupee, is the digital form of sovereign currency issued by the Reserve Bank of India. It is a liability of the central bank, is legal tender, exchanges one for one with the paper rupee and does not earn interest; the wholesale pilot began in November 2022 and the retail pilot in December 2022. Option A is wrong because a cryptocurrency is issued by no authority and its supply and price are set by code and the market, while the digital rupee is issued by the central bank. Option C is wrong because a stablecoin is a private token pegged to an asset, and commercial banks do not issue the digital rupee; they only distribute it. Option D is wrong because a non-fungible token represents a unique item and is not money at all.

The correct answer is C, manufacturing of components and sub-systems. Under the policy amended in 2024, the manufacture of components, systems and sub-systems for satellites and for the ground and user segment is open to foreign direct investment up to 100 per cent through the automatic route, the most liberal of the three groups, because it is a manufacturing activity with the least strategic sensitivity. Option A is wrong because launch vehicles and spaceports are open only up to 49 per cent through the automatic route, government approval being needed beyond that. Option B is wrong because satellite manufacturing and operation and data products stand at 74 per cent automatic. Option D is wrong because the whole point of the amendment was to allow full automatic-route investment in the component segment, where before it the rules were far tighter.