Assertion (A) The velocity of sound in air increases due to the presence of moisture in it.
Reason (R) The presence of moisture in air lowers the density of air.

A. Both A and R are true and R is the correct explanation of A

B. Both A and R are true, but R is not the correct explanation of A

C. A is true, but R is false

D. A is false, but R is true

Answer: Option A