This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Psychiatry
True about Major depressive disorder: 
Select and explain. 
A. Abnormally diminished activity in prefrontal coex, B. Genetic predisposition is present, C. Monoaminergic system disturbances, D. All
D: All
Answer: D: All 
Explanation: A, C, B i.e. Abnormally diminished activity in prefrontal coex, Monoaminergic system disturbances, Genetic predisposition is present