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
Li is best used in - 
Select and explain. 
A. MDP - Bipolar, B. MDP - Unipolar, C. MDP - rapid cycles, D. Depression
A: MDP - Bipolar
Answer: A: MDP - Bipolar 
Explanation: Most important indications of lithium are treatment of acute mania and prophylaxis of bipolar mood disorder, i.e. manic - depressive illness.