Assertion (A): The atmosphere receives most of the heat only indirectly from the sun and directly from the earth's surface.
Reason (R): The conversion from shortwave solar to long-wave terrestrial energy takes place at the earth's surface.

Code:

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

This MCQ is part of the UP PSC Previous Year Questions (PYQs) series, focusing on UPPSC Prelims 1997 (GS Paper I)