This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous system, Subject name: Pharmacology
Lithium is used in the prophylactic treatment of: 
Select and explain. 
A. Schizophrenia, B. MDP, C. Acute depression, D. Conversion reaction
B: MDP
Answer: B: MDP 
Explanation: Lithium is a drug of its own kind to suppress mania and to exe a prophylactic effect in bipolar manic depressive illness (MDI) at doses which have no ove CNS effects. Ref KD Tripati 8th ed.