Answer:
The correct answer is letter "C": clinicians have a clear understanding of the cause of the disorder.
Step-by-step explanation:
Unipolar depression or major depressive disorder (MDD) is the emotional state in which sadness and/or lack of interest controls someone's behavior. Researches state that the most influential factor that provokes depression is in the individual's family tree: genetics. But some of the symptoms of the very same disorder: excess or lack of appetite or not setting a sleeping schedule may trigger depression.