Melanie Thinks She Has Seasonal Affective Disorder

Melanie thinks she has seasonal affective disorder. One finding that would be consistent with this conclusion would be if her doctor found:

A) that she produced melatonin for longer at night in the winter than in the summer.
B) that she produced melatonin for less time at night in the summer than the winter.
C) that she did not produce any melatonin in the winter.
D) that she produced less serotonin in the summer.