The correct option is (c) 2 and 3 only.
Explanation
Water vapour is a variable gaseous constituent of the atmosphere. It plays a fundamental role in atmospheric processes, weather phenomena, and the sustenance of life through the hydrological cycle.
- Statement 1 is Incorrect: Air contains water vapour at all times, not just during the rainy season. The amount of water vapour in the air is known as humidity. While humidity levels fluctuate based on temperature, location, and season (being generally higher in the rainy season and lower in dry seasons), water vapour is never completely absent from the natural atmosphere.
- Statement 2 is Correct: Condensation is the process by which water vapour in the air changes into liquid water. This occurs when warm, moisture-laden air comes into contact with a cooler surface, causing the air to cool below its dew point. Common examples include dew forming on grass or water droplets appearing on the outer surface of a glass containing ice-cold water.
- Statement 3 is Correct: The water cycle (hydrological cycle) relies on the continuous movement of water between the Earth's surface and the atmosphere. Water vapour is the gaseous phase essential for this cycle; water evaporates from water bodies, exists as vapour in the atmosphere, condenses to form clouds, and precipitates back to Earth as rain or snow. Without atmospheric water vapour, this cycle cannot function.
Key Takeaway: Water vapour is a permanent but variable component of the atmosphere present throughout the year, serving as the primary medium for the transfer of moisture and energy in the water cycle.