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Answer: (b)

Explanation:

The Sun is the closest star to the Earth. Among the stars beyond the solar system, Proxima Centauri, part of the Alpha Centauri star system, is the nearest at a distance of about 4.24 light years.

• Sirius, though the brightest star in the night sky, lies about 8.6 light years away.
• Polaris (the North Star) is ~323 light years away.

Hence option (b) is correct.

Answer: (c)

Explanation:

•  Mars has polar ice caps and signs of subsurface water/ice, which makes it a key candidate in the search for extraterrestrial life. Hence statement I is correct.
• The current atmosphere of Mars is too cold and thin to support liquid water, an essential ingredient for life, on its surface for lengthy periods.
• However, various NASA and international missions have found evidence that water was abundant on the Martian surface billions of years ago during a more clement era, such as features that resemble dried-up rivers and lakes, and minerals that only form in the presence of liquid water.
• However, its atmospheric pressure is less than 1% of Earth’s and surface temperatures are extremely low (average −60 °C), making liquid water unstable on the surface. Hence statement II is incorrect.

Therefore, only Statement-I is correct.

Answer- (b)

Explanation:

• Statement 1 is not correct:  The laterite soils develop in areas with high temperature and high rainfall. 
• Statement 2 is not correct: They are the result of intense leaching due to tropical rains. The rain leaches away the lime and silica and therefore, iron oxide and aluminium compounds are left behind in the soil. 
• Statement 3 is correct: These soils are poor in organic matter, nitrogen, phosphate and calcium, while iron oxide and potash are in excess.
  • Humus content of the soil is removed fast by bacteria that thrives well in high temperatures.
• Statement 4 is correct: Red laterite soils in Tamil Nadu, Andhra Pradesh and Kerala are more suitable for tree crops like cashew nuts. 
  • Laterite soils are widely cut as bricks for use in house construction. These soils have mainly developed in the higher areas of the Peninsular plateau.

Answer- (b)

Explanation:

• • About Red Soil: It develops on crystalline igneous rocks in areas of low rainfall in the eastern and southern part of the Deccan Plateau. 
    • Along the piedmont zone of the Western Ghat, a long stretch of the area is occupied by red loamy soil. The soil develops a reddish colour due to a wide diffusion of iron in crystalline and metamorphic rocks. 
    • The fine-grained red soil is normally fertile, whereas coarse-grained soils found in dry upland areas are poor in fertility. It is generally poor in nitrogen, phosphorus and humus.

• Hence option (b) is the correct answer.

SOURCE:

https://ncert.nic.in/ncerts/l/kegy106.pdf

Answer- (d)

Explanation:

• • About Disaster Management Act, 2005: It was enacted in the wake of the 1999 Odisha super-cyclone and the 2004 tsunami. It defines a disaster as a “catastrophe, mishap, calamity or grave occurrence” arising from “natural or man-made causes” that results in substantial loss of life, destruction of property, or damage to the environment. 
  • Disasters included in Disaster Management Act, 2005: Currently, there are 12 categories of disasters which are notified under this Act. 
    • These are cyclones, drought, earthquake, fire, flood, tsunami, hailstorm, landslide, avalanche, cloudburst, pest attack, and frost and cold waves. However, the heatwave is not a notified disaster in India.
• Hence option (d) is the correct answer.