Analyzing Assertion (A): Moist Air Parcel Behavior

Assertion (A) states that under adiabatic conditions, a moist air parcel cools more slowly and rises to a greater height compared to a dry air parcel. This is accurate. As a moist air parcel rises, it expands and cools adiabatically. If it cools to its dew point, water vapor condenses.

The process of condensation releases latent heat. This released heat partially counteracts the adiabatic cooling, causing the moist parcel to cool at a slower rate than a dry parcel experiencing only adiabatic cooling.

Analyzing Reason (R): Latent Heat's Effect

Reason (R) explains that the latent heat of condensation released within a moist air parcel reduces its rate of cooling under adiabatic conditions, compared to dry air. This statement correctly identifies the physical mechanism.

The addition of heat from condensation makes the moist parcel warmer (or cooler at a reduced rate) than a dry parcel undergoing pure adiabatic expansion and cooling at the same altitude.

Evaluating the Relationship

Because the moist air parcel cools more slowly due to latent heat release (Reason R), it maintains its buoyancy for longer. This allows it to ascend to a higher altitude before its density matches the surrounding air, validating Assertion (A).

Therefore, Reason (R) accurately explains why Assertion (A) is true.

Conclusion

Both Assertion (A) and Reason (R) are correct, and Reason (R) is the correct explanation of (A).