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
[{'content': 'Treatment of choice for prophylaxis in patients with repeated episodes of bipolar illness: March 2004 \nSelect and explain. \nA. Lithium, B. Valproate, C. A + B, D. None of the above', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. C i.e. A + B Ref: Kumar and Clark's", 'role': 'assistant'}]