This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Drugs, Subject name: Medicine
[{'content': 'Hirsutism is caused by: \nSelect and explain. \nA. Minoxidil, B. Propranolol, C. Calcium channel blockers, D. Sodium nitroprusside', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans: aRef: Harrison, 16,hed, p. 276, Table 44.1', 'role': 'assistant'}]