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
Drug of choice for rapid cyclers is 
Select and explain. 
A. Lithium, B. Sodium valproate, C. Carbamazepine, D. Amitryptaline
B: Sodium valproate
Answer: B: Sodium valproate 
Explanation: Sodium valproate is the drug of choice for rapid cyclers.
Rapid cyclers has 4 or more than 4 episodes of mania, depression or hypomania in 1 year.