Question

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): Western Rajasthan region suffers from chronic deficiency of water and frequent droughts.
Reason (R): Western Rajasthan is a region of low average annual rainfall and also of low average annual variability of rainfall.
In the light of the above statements, choose the most appropriate answer from the options given below:

• A. Both (A) and (R) are correct and (R) is the correct explanation of (A)
• B. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
• C. (A) is correct but (R) is not correct
• D. (A) is not correct but (R) is correct

Hint:

Rule of Thumb: Lower the total rainfall, higher the variability (unreliability).

Answer 1

The Correct Option is C

Concept: The climate of Western Rajasthan (the Thar Desert) is defined by its aridity. Drought in this region is a product of both low total rainfall and the high uncertainty of when that rain will fall.

Step 1: Analyzing the Water Crisis (A).
Western Rajasthan is one of the most arid regions in India. It receives less than 25 cm of rainfall annually in many parts. The high evaporation rates and lack of perennial rivers lead to chronic water scarcity and frequent agricultural and hydrological droughts. Assertion (A) is correct.

Step 2: Analyzing Rainfall Variability (R).
In climatology, there is a fundamental rule: regions with very low average rainfall usually have very high annual variability. This means that if the average is 20 cm, one year might see 40 cm and the next year only 5 cm. Reason (R) states the region has "low average annual variability," which is factually incorrect. The variability in the Thar Desert is among the highest in India.

Step 3: Conclusion.
Droughts are frequent specifically *because* the variability is so high—the rain is unreliable. Since (R) misstates the nature of rainfall variability, the statement (R) is false.