There are two statements marked as Assertion (A) and Reason (R). Mark your answer as per the options given below.

Assertion: Bipolar I disorder involves both mania and depression, which are alternately present and sometimes interrupted by periods of normal mood.
Reasoning: Bipolar mood disorders were earlier referred to as manic-depressive disorders.

Both Assertion (A) and reasoning (R) are correct but R is not the correct explanation of A.

Bipolar I disorder involves both mania and depression, which are alternately present and sometimes interrupted by periods of normal mood. Manic episodes rarely appear by themselves; they usually alternate with depression. Bipolar mood disorders were earlier referred to as manic-depressive disorders.