This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: D.O.C, Subject name: Pharmacology
[{'content': 'Drug of choice for prophylaxis of TB is?(DNB 2012-section-1) \nSelect and explain. \nA. Rifampicin, B. Isoniazid, C. Pyrizinamide, D. Streptomycin', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (b) IsoniazidRef .KDT 6/e / 740-743', 'role': 'assistant'}]