Answer: C

Exp:

Recently, the National Green Tribunal (NGT) ordered the Central Ground Water Board (CGWB) to investigate the contamination of groundwater in the Sukinda Valley of Odisha’s Jajpur district where groundwater samples have been found to be contaminated with dangerous levels of chromium.

About Heavy Metals:

• Heavy metals are elements with an atomic number greater than 20 and an atomic density exceeding 5 g/cm³, exhibiting metallic properties. 
• Examples include arsenic, cadmium, chromium, copper, lead, manganese, mercury, nickel, and uranium. Hence, option (c) is correct.
• Selenium: It is a non-metal with an atomic weight of 34 and is intermediate with Sulphur and Tellurium with actions of a metalloid.

Heavy Metal Pollution:

• Causes:
  • Rapidly growing agriculture and metal industries
  • Improper waste management
  • Heavy use of fertilizers and pesticides
• Primary Sources:
• • Agricultural and industrial operations.
  • Landfilling.
  • Mining.
  • Transportation.

Answer: A

Exp

An Indian Air Force (IAF) contingent landed at the Royal Australian Air Force (RAAF) Base Darwin, Australia for participating in Exercise Pitch Black 2024.

India’s Military Exercises:

• Exercise Pitch Black 2024: The exercise is scheduled to be conducted from 12 July 24 to 02 August 24, and is a biennial, multi- national exercise hosted by the RAAF. 
  • The name ‘Pitch Black’ was derived from the emphasis on night time flying over large un-populated areas. Thus, 1st Pair is correctly matched.
• Hand-in-Hand: It is an annual exercise that takes place as part of India’s and China’s military diplomacy and interaction. The simulation involves tactical activities in a UN-mandated worldwide counterinsurgency/counterterrorism scenario. Thus, 2nd Pair is incorrectly matched.
• Surya Kiran Exercise: It is the bilateral joint military Exercise between India and Nepal to enhance interoperability in jungle warfare & counterterrorism operations in mountainous terrain. Thus, 3rd Pair is incorrectly matched. 

Answer: D

Exp

Scientists call for studies on risks and benefits of glacial geoengineering to slow sea-level rise.

Glacial Geoengineering:

• Glacial geoengineering involves deliberate interventions aimed at mitigating the effects of climate change on glaciers and ice sheets. 
• The primary goals are to slow down ice melt, stabilize glaciers, and reduce sea level rise.
• While various climatic geoengineering approaches have been considered, serious consideration of geotechnical approaches has been limited.
• Here are some key methods and concepts which can be used in Glacial geoengineering:
  • Draining or freezing the bed. 
  • Altering surface albedo. 
  • Creating obstacles: retaining snow. 
  • Stiffening shear margins with ice. 
  • Blocking warm sea water entry. 
  • Thickening ice shelves (increasing buttressing, and strengthening fractured shelves against disintegration). 
  • Using regional climate engineering or local cloud seeding to cool the glacier or add snow. Hence, option (d) is correct.

Answer: B

Exp:

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) has issued guidelines for its members involved in the sustainable harvest and trade of rosewood specimens.

About Rosewood:

• Rosewood: It is a luxurious and highly prized wood known for its rich, reddish-brown color and fine grain. 
  • Native to the Americas and Southeast Asia, rosewood is often used to create high-end furniture, musical instruments, and luxury items due to its unique appearance and exceptional durability.
• Statement 1 is incorrect: CITES oversees the international trade of various rosewood species, including those in the genera Dalbergia, Afzelia, Khaya and Pterocarpus. 
  • Currently, these species are listed in Appendix II, indicating they are not immediately threatened with extinction but could be at risk if their trade is not regulated.
• Statement 2 is correct: Dalbergia sissoo is commonly known Rosewood, Shisham and is a medium to large deciduous tree, native to India, with a slight crown.
  • Distribution: It is native to the foothills of the Himalayas. It is primarily found growing along river banks below 900 metres elevation.

Answer: D

Exp:

Researchers have found an eco-friendly approach that can eliminate the use of toxic chemicals in silk processing. 

About Silk:

• Statement 1 is correct: Silk is a natural fiber produced by silkworms. It is made from the cocoons spun by the larvae of the silk moth, known scientifically as Bombyx mori. 
• Statement 2 is correct: Sericulture is the practice of cultivating silkworms for the production of silk. 
  • It involves breeding and raising silkworms, as well as harvesting and processing their cocoons to extract the silk fibers. 
  • Sericulture has been an important industry for thousands of years, particularly in Asia, where it is used to produce high-quality silk fabrics. 
• Statement 3 is correct: Traditionally, toxic chemicals like sodium carbonate, sodium hydroxide, sulfuric acid, and lithium bromide have been used to extract silk proteins, fibroin and sericin from various types of raw silk fibers, an important step in the process of making silk from cocoons.