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
Lithium is treatment of choice for -
a) Unipolar MDP prophylaxis
b) Bipolar MDP prophylaxis
c) Schizophrenia
d) Acute mania 
Select and explain. 
A. abc, B. bd, C. bcd, D. ac
B: bd
Answer: B: bd 
Explanation: Most important indications of lithium are treatment of acute mania and prophylaxis of bipolar mood disorder, i.e. manic - depressive illness.