UPSC CSE Prelims
Question 45
With reference to "water vapour", which of the following statements is/are correct ?
- It is a gas, the amount of which decreases with altitude.
- Its percentage is maximum at the poles.
Select the answer using the code given below :
View correct answer and explanation
Correct answer: A
Correct Option: A (1 only)
Explanation: Atmospheric water vapour is concentrated in warm lower air and declines with altitude; it is generally highest in tropical regions, not polar ones.
Statement / Pair / Item-wise Analysis:
1. Correct/True - Most atmospheric moisture lies near the surface and decreases with elevation.
2. Incorrect/False - Cold polar air holds much less water vapour than warm tropical air.
Option-wise Analysis:
A. Correct-includes precisely the true/correct statements or pairs identified above.
B. Incorrect-incorrectly includes 2 (Cold polar air holds much less water vapour than warm tropical air.); omits correct item 1 (Most atmospheric moisture lies near the surface and decreases with elevation.).
C. Incorrect-incorrectly includes 2 (Cold polar air holds much less water vapour than warm tropical air.).
D. Incorrect-omits correct item 1 (Most atmospheric moisture lies near the surface and decreases with elevation.).