Solution (d)

Explanation:

• A deuteron is a stable isotope of hydrogen with a nucleus containing one proton and one neutron. It is denoted by the symbol “²H” or “D”. It is found in small amounts in natural water and in the atmosphere of Jupiter and Saturn. The mass of a deuteron is approximately about twice the mass of a proton. Hence, statements 1 and 2 are correct.

Deuteron is used in the production of heavy water, which is used as a moderator in nuclear reactors. It is used in the production of deuterium, which is used as a fuel in fusion reactors. It is also used in the production of tritium, which is used in nuclear weapons. Hence, statement 3 is correct.

Solution (b)

Explanation:

• The Sea of Japan, or East Sea, is a marginal sea of the western Pacific Ocean. It is bound by Japan and Sakhalin to the east and by mainland Russia, North Korea, and South Korea to the west. It is connected with the East China Sea via the Tsushima and Korea straits and with the Okhotsk Sea in the north by the La Perouse and Tatar straits. In the east, it is connected with the Inland Sea of Japan via the Kanmon Strait and the Pacific Ocean by the Tsugaru Strait. Hence, statements 1 and 2 are correct.

Like the Mediterranean Sea, it has almost no tides due to its nearly complete enclosure from the Pacific Ocean. The sea is known for its high concentration of oxygen (dissolved in the seawater), which results in high biological productivity. Hence, statement 3 is not correct.

Solution (a)

Explanation:

• Shri Mahakaleshwar Temple is a Hindu temple located on the banks of the River Shipra at Ujjain in Madhya Pradesh. It is dedicated to Lord Shiva. It is one of the 12 Jyotirlingas in India. It is the only Jyotirlinga that faces south (Dakshinamukhi), a unique feature associated with Tantric traditions where Shiva is considered the ‘Lord of Time and Death’. Hence, statement 1 is INCORRECT.

• The current structure of the temple was built in the 18th century by the Maratha ruler Ranoji Shinde. However, the temple has been destroyed and rebuilt several times throughout history. The architecture of the temple shows the influence of Maratha, Bhumija, and Chalukya styles of structural design. Hence, statement 2 is correct.

Solution (c)

Explanation:

Model Youth Gram Sabha is a simulated forum for school children to participate in mock Gram Sabha sessions. It is a pioneering initiative to strengthen Janbhagidari and promote participatory local governance by engaging students in simulated Gram Sabha sessions. It is an initiative of the Ministry of Panchayati Raj, in collaboration with the Ministry of Education and the Ministry of Tribal Affairs. Hence, statements 1 and 2 are correct.

Solution (a)

Explanation:

Hoya Nagaensis is a new plant species found in the high-altitude forests of Nagaland. It is a member of the ‘wax plant family’ discovered in the Kavunhou Community Reserved Forest in Phek district. It belongs to the Hoya genus, a group known for its ornamental value. It is currently known from only a single location, making it highly vulnerable. Hence, option a is the correct answer.