With reference to "water vapour", which of the following statements is/are correct? 1. It is a gas, the amount of which decreases with altitude. 2. Its percentage is maximum at the poles. Select the answer using the code given below:

Answer: A. Statement 1 only is correct. Statement 1 is CORRECT. Water vapour is concentrated in the LOWER troposphere; about 90% of it sits below 5 km altitude. The amount declines steeply with height because cooler air at higher altitudes can hold far less moisture. Statement 2 is INCORRECT. The percentage of water vapour is MAXIMUM AT THE EQUATOR (warm air, intense evaporation from tropical oceans) and MINIMUM at the poles, where cold air holds very little moisture. The claim reverses the geography. Source: NCERT Class 11 Fundamentals of Physical Geography, Ch 8 (Composition and Structure of the Atmosphere).