Answer:  Option A - Primarily composed of carbon dioxide with extreme surface temperatures

Explanation:

• Venus' atmosphere is primarily composed of carbon dioxide, accounting for about 96%, with trace amounts of nitrogen and other gases.
• The thick carbon dioxide layer, along with clouds of sulfuric acid, traps heat, creating an intense greenhouse effect.
• This causes surface temperatures to exceed 460°C, making Venus the hottest planet in the solar system.
• The dense atmosphere also results in surface pressures about 92 times higher than Earth's.

Answer:  Option B - Rising sea levels threatening its atolls and sovereignty

Explanation:

• The primary existential crisis faced by Tuvalu is the rising sea levels, which threaten its low-lying atolls and sovereignty.
• As a small island nation, projections suggest that half of its main atoll, Funafuti, could be submerged by 2050.
• This has resulted in groundwater contamination, agricultural decline, and forced migration.
• Tuvalu is seeking international support for legal recognition of its maritime boundaries to preserve its territorial integrity and ensure sovereignty.

Answer:  Option D - Lunar sample return

Explanation:

• China's Chang’e-5 mission, is a lunar sample return mission aimed at collecting and bringing back soil and rock samples from the Moon.
• It marked China's first successful attempt at retrieving lunar material, making China the third country to achieve this after the United States and the Soviet Union.
• The mission was a significant step in advancing China's lunar exploration and space capabilities.

Answer:  Option C - USA

Explanation:

• India is acquiring the Apache Helicopter (AH-64E) from the USA, specifically developed by Boeing.
• This multi-role attack helicopter is equipped with advanced systems for various combat scenarios, including close air support and anti-armour operations.
• The acquisition enhances India's military capabilities, particularly in terms of modern avionics and target acquisition systems, contributing to the country's defence preparedness and strategic objectives in a complex security environment.

Answer:  Option B - The formal withdrawal of a published scientific paper due to inaccuracies.

Explanation:

• Retraction in scientific literature refers to the formal withdrawal of a published paper due to significant errors, ethical concerns, or misconduct, such as plagiarism or falsified data.
• This process aims to maintain the integrity of scientific communication by correcting the public record.
• Retractions are typically issued by the authors or the journal's editorial board and serve as a crucial mechanism for ensuring accountability and trust within the scientific community.