How many additive manufacturing start-ups have been supported so far under NSAM?

The correct answer is the Ministry of Electronics and Information Technology (MeitY). MeitY brought out the National Strategy for Additive Manufacturing in February 2022 as the guiding policy framework for 3D printing in India, keeping it aligned with Make in India and Atmanirbhar Bharat. The same ministry supports the specialised Development and Deployment Centres and organised the second National Additive Manufacturing Symposium in New Delhi. Option A, the Ministry of Heavy Industries, sounds plausible because additive manufacturing makes machine parts, but the strategy is not its document. Option C, the Ministry of Science and Technology, is wrong here, although the Council of Scientific and Industrial Research works under it and organises the ESTIC conclave where additive manufacturing features. Option D, the Ministry of Commerce and Industry, deals with trade and investment promotion and had no role in issuing this strategy.

The correct answer is 5 per cent. The national strategy sets a time-bound goal of capturing a twentieth of the world additive manufacturing market and of adding close to one billion US dollars to India's gross domestic product. Around that headline figure sit its other targets: 50 technologies built for Indian needs covering materials, machines, processes and software, 100 new start-ups, 500 new products, a skilled pool of one lakh workers and additive manufacturing capability in 10 existing and emerging manufacturing sectors. Option A understates the ambition, while options C and D overstate it; no such share appears in the strategy. The figure matters because progress is measured against it, and the next phase, NSAM 2.0, is being shaped to accelerate the market further.

The correct answer is the Council of Scientific and Industrial Research (CSIR). ESTIC is India's Emerging Science, Technology and Innovation Conclave, and its second edition is organised by CSIR on the theme 'Creative Minds, Catalyzing Science, Empowering Technologies'. The conclave spans 12 thematic areas with plenary sessions, technical discussions and exhibitions, takes forward frontier fields such as additive manufacturing, and supports the vision of Viksit Bharat 2047. Option A, ISRO, is the space agency and is linked to additive manufacturing only through printed rocket hardware. Option B, DRDO, handles defence research and is not the organiser. Option D, ICAR, is the apex agricultural research body and has no role in this conclave. Note the venue, Bharat Mandapam in New Delhi, and the dates.

The correct answer is 3.89 billion solar masses. Using eight optical spectra recorded at Steward Observatory in the United States during low-brightness phases of the object in October and November 2017, the team estimated the central black hole to weigh no less than that, reading the figure from the width of the oxygen emission line. Option A is wrong because it shifts the same digits down by a factor of a thousand; supermassive black holes can range from millions to billions of solar masses, so a candidate who misses the unit will fall for it. Option C is wrong because eighteen is the number of countries whose scientists joined the study, not a mass. Option D is wrong for the same kind of reason, since one hundred and six is the number of scientists in the team. The lesson is to keep the three large numbers of this study separate: the team size, the number of countries and the mass estimate.

The correct answer is twelve years. OJ 287 is a rare object lying about 4 billion light years away in which two supermassive black holes circle each other on a twelve-year orbit, forming a binary system. Because of that orbit the blazar brightens in a distinctive double peak, a rhythm that Finnish scientists identified in 1988 after studying nearly 100 years of optical observations going back to 1880, and astronomers have since followed each twelve-year cycle of twin outbursts to map the motion. The recent campaign captured the outbursts that fell between 2015 and 2019. Options A, B and D are wrong because none of them matches the period of the pair; they are included because a candidate who remembers only that the object has a repeating cycle may guess at the number. Remember the orbital period along with the distance, as the two facts are usually asked together.