(d) EXPLANATION: ■ Open-source software (OSS) is computer software that is released under a license in which the copyright holder grants users the rights to use, study, change, and distribute the software and its source code to anyone and for any purpose. ■ DIKSHA: DIKSHA (Digital Infrastructure for Knowledge Sharing) is a national platform for school education, an initiative of National Council for Education Research and Training (NCERT), Ministry of Education. DIKSHA was developed based on the core principles of open architecture, open access, open licensing diversity, choice and autonomy as outlined in the Strategy and Approach Paper for the National Teacher Platform released in 2017. ■ DigiLocker is an initiative by the government to offer Indian citizens a free platform to store and access important documents. The platform uses several open source technologies to deliver a mass solution and contributes back to the ever-growing community. ■ COWIN: CoWIN is an Indian government web portal for COVID-19 vaccination registration, owned and operated by India’s Ministry of Health and Family Welfare. Initially it was not an open-source digital platform, but in July, 2019 it was made open source. ■ Aarogya Setu: On 2nd April 2020, India launched Aarogya Setu mobile App for helping augment the efforts of limiting the spread of COVID19, with an objective of enabling Bluetooth based contact tracing, mapping of likely hotspots and dissemination of relevant information about COVID19. It is open source now.

(d) EXPLANATION: ■ The concept of Web3, also called Web 3.0, is used to describe a potential next phase of the internet. ■ The model, a decentralised internet to be run on blockchain technology, would be different from the versions in use, Web 1.0 and Web 2.0. ■ Web3 enables peer to peer (seller to buyer) transactions by eliminating the role of the intermediary. ■ In web3, users will have ownership stakes in platforms and applications unlike now where tech giants control the platforms. ■ Web3 will deliver a decentralized and fair internet where users control their own data.

(d) EXPLANATION: ■ Software-as-a-Service (SaaS) is a software licensing model. ■ It allows access to software on a subscription basis using external servers. ■ As its important feature, SaaS allows each user to access programs via the Internet. ■ Thus, SaaS allows data to be accessed from any device (computer or mobile phones) with an internet connection and a web browser. ■ The user need not install the software on his/her computer. ■ In simple words, software-as-a-Service (SaaS)—also known as cloud based software—is now mainstream. ■ Today’s web-based software (SaaS) is flexible enough to be modified for specific business uses but also individual users. ■ Buyers can customize the user interface (UI) to change the look and feel of the program, as well as modify specific areas, such as data fields, to alter what data appears. ■ Several business process features can also be turned off and on at will. ■ Any web-based email service is classified as SaaS, examples a web-based email service such as Outlook, Hotmail or Yahoo!.

(c) EXPLANATION: In October 2021, China was suspected to have tested Fractional Orbital Bombardment System. ■ A Fractional Orbital Bombardment System (FOBS) is a warhead delivery system that uses a low earth orbit towards its target destination. ■ Just before reaching the target, it deorbits through a retrograde engine burn. ■ The flight path of the warhead from the system does not reveal the target location till the payload hits the destination.

(b) EXPLANATION: ■ Quantum computing holds the promise to solve some of our planet’s biggest challenges – in the areas of environment, agriculture, health, energy, climate, materials science, and others we haven’t encountered yet. ■ For some of these problems, classical computing is increasingly challenged as the size of the system grows. ■ Just as bits are the fundamental object of information in classical computing, qubits (quantum bits) are the fundamental object of information in quantum computing. ■ While a bit, or binary digit, can have a value either 0 or 1, a qubit can have a value that is either 0, 1 or a quantum superposition of 0 and 1.

(d) EXPLANATION: ■ Short Range Devices (SRD) are radio devices that offer a low risk of interference with other radio services, usually because their transmitted power, and hence their range, is low. ■ The definition ‘Short Range Device’ may be applied to many different types of wireless equipment, including various forms of: Access control (including door and gate openers) Alarms and movement detectors Closed-circuit television (CCTV) Cordless audio devices, including wireless microphones Industrial control Local Area Networks Medical implants Metering devices Remote control Radio frequency identification (RFID).

(d) EXPLANATION: ■ Biofilm is a thin usually resistant layer of microorganisms (as bacteria) that forms on and coats various surfaces (as of catheters or water pipes). ■ These cells are frequently embedded within a self-produced matrix of extracellular polymeric substance (EPS). ■ Biofilms can form on just about any imaginable surface: metals, plastics, natural materials (such as rocks), medical implants, kitchen counters, contact lenses, the walls of a hot tub or swimming pool, human and animal tissue, including medical devices and implants. ■ They are a constant concern in food processing environments. ■ Biofilms of Lactobacillus curvatus could lead to a defect caused by the formation of calcium lactate crystals in Cheddar cheese and they can be present on equipment surfaces (tough to remove). ■ Bacteria form biofilms, a kind of matrix, during infection in plants and animals. ■ The biofilm shields the bacteria from antibiotics and helps bacteria survive harsh conditions such as extreme temperature or stress. Thus they can exhibit antibiotic resistance.

(c) EXPLANATION: ■ Probiotics are live microorganisms (bacteria and yeasts can form an important part of the human mycobiome as probiotics.) that are intended to have health benefits when consumed or applied to the body. ■ They can be found in yogurt and other fermented foods, dietary supplements, and beauty products. Hence statement 1 is correct. ■ Although people often think of bacteria and other microorganisms as harmful “germs,” many are actually helpful. ■ Some bacteria help digest food, destroy disease-causing cells, or produce vitamins. ■ Many of the microorganisms in probiotic products are the same as or similar to microorganisms that naturally live in our bodies. Hence statement 2 is not correct. ■ There is evidence that probiotics can alleviate symptoms of lactose intolerance. ■ This can occur by increased hydrolysis (breaking down or digestion) of lactose (milk sugar) in the dairy product and in the small intestine. ■ It can also be achieved by manipulation of the colonic metabolism. Hence statement 3 is correct.

(b) EXPLANATION: ■ Covishield and Covaxin were the first vaccines permitted to be administered to people in India in the first half of 2021. Sputnik came weeks later. ■ Covishield: It is not an mRNA-based vaccine. Covishield (produced by Serum Institute of India) is a recombinant, replication-deficient chimpanzee adenovirus vector encoding the SARS-CoV-2 Spike (S) glycoprotein. Following administration, the genetic material of part of corona virus is expressed which stimulates an immune response. Hence statement 1 is not correct. ■ Covaxin: It is an indigenous, inactivated pathgen type vaccine developed and manufactured in Bharat Biotech’s BSL-3 (Bio-Safety Level 3) high containment facility. The vaccine is developed using Whole-Virion Inactivated Vero Cell derived platform technology. Hence statement 3 is correct. ■ Sputnik V: It is an adenovirus viral vector vaccine for COVID-19 developed by the Gamaleya Research Institute of Epidemiology and Microbiology in Russia. It is the world’s first registered combination vector vaccine for the prevention of COVID-19, having been registered on 11 August 2020 by the Russian Ministry of Health. Hence statement 2 is correct.

(c) EXPLANATION: ■ Solar flares occur when magnetic energy builds up in the solar atmosphere and is released suddenly. ■ These outbursts are intrinsically linked to the solar cycle — an approximately 11-year cycle of solar activity driven by the sun’s magnetic field. ■ These are large explosions from the surface of the sun that emit intense bursts of electromagnetic radiation. ■ Harmful radiation from a flare cannot pass through Earth’s atmosphere to physically affect humans on the ground. ■ The solar flares, even the intense ones, do not pose an immediate threat to us, at least those who are within the Earth’s atmosphere. ■ Flares are not fires but outbursts of electromagnetic radiation. ■ Thus they will not cause forest fires. ■ Tsunami is a purely seismic phenomenon. ■ Earthquakes, volcanic eruptions and other underwater explosions (including detonations, landslides, glacier calvings, meteorite impacts and other disturbances) above or below water all have the potential to generate a tsunami and not solar flares. ■ Strong M-class and X-class solar flares can trigger coronal mass ejections — a large release of plasma and magnetic field from the sun. ■ This behavior can disrupt Earth’s magnetosphere and result in geomagnetic storms. ■ Such geomagnetic storms can lead to auroras closer to the equator than is possible during calm conditions. Hence statement 4 is correct. ■ Known as a coronal mass ejection or CME these solar explosions propel bursts of particles and electromagnetic fluctuations into Earth’s atmosphere. ■ Those fluctuations could induce electric fluctuations at ground level that could blow out transformers in power grids. ■ A CME’s particles can also collide with crucial electronics onboard a satellite and disrupt its systems. It may lead to high-frequency communication blackouts, satellite anomalies, GPS scintillations, airline communication impacts.

(d) EXPLANATION: ■ The primary and secondary immune responses are carried out with the help of two special types of lymphocytes present in our blood, i.e., B-lymphocytes (B-cells) and T-lymphocytes (T-cells). ■ Thus, both B-cells and T-cells are responsible for acquired immunity. ■ B-cells are responsible for antibody-mediated immunity response. ■ T-cells are responsible for cell-mediated immunity response. ■ B cells produce antibodies to fight with the pathogens into our blood. ■ The T-cells themselves do not secrete antibodies but help B cells produce them.

(d) EXPLANATION: ■ Nanoparticles occur widely in nature and are objects of study in many sciences such as chemistry, physics, geology and biology. ■ A significant fraction (by number, if not by mass) of interplanetary dust, that is still falling on the Earth at the rate of thousands of tons per year, is in the nanoparticle range; and the same is true of atmospheric dust particles. ■ Many viruses have diameters in the nanoparticle range. Iron oxides/sulfides, silver, and gold are some of the representative examples of naturally-occurring nanoparticles in the environment. Hence statement 1 is not correct. ■ Many cosmetic products used in our daily life are made with the assistance of nanotechnologies. ■ Among metal and metal oxide nanoparticles (NPs) potentially present in cosmetics, those containing titanium dioxide and zinc oxide are common ingredients added to obtain a sufficient sun protection. ■ The addition of silver and gold NPs is also mentioned to increase the antimicrobial and healing properties of some cosmetic formulations. Hence statement 2 is correct. ■ The exposure of nanoparticle to environment and human can be described through different mechanisms. ■ Primarily occupational exposures occur to workers (including engineers, scientists, and technicians) during the research-scale synthesis and commercial production of nanomaterial-based products. ■ This exposure mainly results from handling of raw materials while carrying out reactions through the equipment. ■ Characterization of resulting material, packing, and transportation can be other sources of this type of exposure. ■ At the second stage, consumers are exposed to such nanomaterial during usage and application and it may lead to harmful and toxic effects. Hence statement 3 is correct.

(d) EXPLANATION: ■ DNA barcoding is the identification of a species by the characteristic sequence of a standard short section of DNA in its genome. ■ DNA barcoding is done by comparing an individual DNA sequence with a reference library of such DNA sections (called sequences). ■ The introduction of DNA barcoding represents a promising approach for food authentication, being broadly applied in fish species. ■ DNA barcoding has been successful when applied to seafood because the number of species is high in comparison to other animal sources, such as cattle, sheep, goat, and horse, enhancing the effectiveness of the approach. ■ DNA barcoding techniques were used to explore the composition of roasted barley tea (Hordeum vulgare), which was exported to a certain country from China but then returned, due to the detection of other undesirable plant components present or contaminants were found. ■ DNA barcoding will allow users to efficiently recognize known species and speed the discovery of species yet to be found in nature. ■ There have been reports of DNA barcodes used in distinguishing species of tropical Lepidoptera (an order of insects that includes butterflies and moths which are similar). ■ DNA barcodes effectively distinguish among species in three Lepidoptera families from Area de Conservación Guanacaste in northwestern Costa Rica. ■ However, DNA barcoding is not known to be used for the assessment of age of living organisms. Hence option 1 is not correct.