With reference to 'water vapour in the atmosphere', which of the following statements is/are correct?

I. It contributes to the stability and instability in the air.

II. It acts like a blanket, allowing the Earth neither to become too cold nor too hot.

Select the answer using the code given below.

Both statements are correct based on atmospheric science. Statement I is correct because water vapour is the carrier of latent heat. The absorption of heat during evaporation and its release during condensation are the primary drivers of atmospheric instability (leading to clouds and storms) and stability, depending on the vertical temperature profile and moisture content.

Statement II is correct because water vapour is a potent greenhouse gas. It absorbs a portion of incoming solar radiation and, more significantly, traps outgoing long-wave terrestrial radiation. This creates a "blanket effect" that prevents the Earth from cooling down excessively at night or heating up too intensely during the day, thereby maintaining a habitable temperature range.