Answer: c

Explanation:

For the past week, Mount Etna, Europe's largest volcano and one of the most active and renowned worldwide, has been emitting nearly flawless rings of smoke into the atmosphere. These rare formations, resembling smoke rings, occur when gas, mainly water vapor, is rapidly released through a vent in the volcano's crater. The circular shape of the rings above Mount Etna, observed since April 2, is attributed to the almost perfectly circular vent opening. Vortex rings, also known as toroidal vortexes, are torus-shaped regions within a fluid where the majority of the fluid spins around an imaginary axis forming a closed loop. While abundant in turbulent flows of liquids and gases, vortex rings are typically unnoticed unless revealed by suspended particles, such as smoke rings produced by smokers or fiery vortex rings created by fire eaters. Hence, statement 1 and 2 are correct.

Vortex rings can be observed in various phenomena, including certain artillery firing, mushroom clouds, microbursts and occasionally in volcanic eruptions. These rings tend to move perpendicular to their plane, with the inner edge moving faster forward than the outer edge. In a typical vortex ring, fluid particles move in circular paths around an imaginary core that is perpendicular to these paths. The velocity of the fluid is relatively constant except near the core, where the angular velocity increases, concentrating most of the vorticity and energy dissipation. Similar to a rotating wheel reducing friction between a car and the ground, the poloidal flow of the vortex reduces friction between the core and the surrounding fluid, allowing it to travel long distances with minimal loss of mass and kinetic energy. Hence, statement 3 is correct.

Answer: c

Explanation:

A recent public rally in Rajasthan stirred controversy when Congress president Mallikarjun Kharge mentioned Article 371. India adopted quasi-federalism to accommodate diverse identities, religions, and languages, ensuring harmony between the Union and State governments. Article 371 provides special powers to 12 other States, including Arunachal Pradesh, Gujarat, Maharashtra, Manipur, Nagaland and Sikkim. These provisions, listed under Articles 371 (A-J) in Part XXI of the Constitution, were incorporated through subsequent amendments. Hence, statement 1 is correct.

Article 371(A) and (B) focus on Maharashtra and Gujarat, respectively, mandating the establishment of separate development boards for specific regions within these States. Article 371(A) was added in 1962, granting special provisions to Nagaland, including autonomy over religious and social practices, customary laws, and land ownership. Hence, statement 2 is correct.

Article 371(B) addresses Assam's tribal areas, later forming the basis for the creation of the State of Meghalaya. Article 371(C) applies to Manipur, involving the constitution of a legislative committee for the Hill Areas and granting the Governor special responsibilities. Articles 371(D) and (E) include special provisions for Andhra Pradesh, focusing on equitable opportunities in employment and education, establishment of an Administrative Tribunal, and the creation of local cadres. Hence, statement 3 is correct.

Answer: c

Explanation:

The government introduced CDP-SURAKSHA, a platform for disbursing subsidies to horticulture farmers under the Cluster Development Programme (CDP). A team of international researchers compiled the 'World Cybercrime Index' ranking around 100 countries based on various cybercrime categories. The index suggested that cybercriminal threats originated from a small number of countries, with China, Russia, Ukraine, the US, Romania and Nigeria consistently ranking high. 97 countries were named as hubs for specific cybercrime categories.

Russia ranked first in cybercrime, followed by Ukraine, China, the US, Nigeria and Romania. North Korea, the UK and Brazil held the seventh, eighth and ninth positions, respectively. India secured the tenth spot in cybercrime rankings. Hence, option (c) is correct.

Answer: c

Explanation:

Recently, the researchers at the Indian Institute of Science (IISc) have designed a sustainable hydrogel to remove microplastics from water. Hydrogel, also known as aqua gel is a three-dimensional network of polymer chains that can absorb and retain large amounts of water.

It has a unique intertwined polymer network designed to bind and degrade microplastic contaminants using UV light irradiation. Hence, statement 1 is correct.

Unlike traditional filtering membranes, which can become clogged with microplastics, the hydrogel offers a sustainable solution for microplastic removal. It consists of chitosan, polyvinyl alcohol and polyaniline layers intertwined to form an interpenetrating polymer network (IPN) architecture. The hydrogel matrix is infused with nanoclusters of a material called copper substitute polyoxometalate (Cu-POM), which act as catalysts for degrading microplastics under UV light. Hence, statement 2 is correct.

Answer: c

Explanation:

Recently, new evidence from the Australian Marine Conservation Society revealed that the coral bleaching observed earlier this year in the southern part of the Great Barrier Reef is far worse than expected. Coral bleaching is a process that occurs when corals expel the algae that live inside their tissues, causing them to turn white. Hence, statement 1 is correct.

The algae, called zooxanthellae, provide nutrients to the corals through photosynthesis and give them their characteristic colors. This happens when coral polyps experience a stress event, such as: Extreme salinity, Pollution, Overfishing Sedimentation and Warmer water temperatures. Hence, statement 2 is correct.