Assertion (A): When light falls at junction of p-n photodiode, its p side becomes positive and n side becomes negative.Reason (R): When a photodiode is short circuited, the current in the external circuit flows from p side to n side.

• A. Both A and R are true and R is correct explanation of A
• B. Both A and R are true but R is not a correct explanation of A
• C. A is true but R is false
• D. A is false but R is true