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: Pharmacology
[{'content': 'Which of the following drugs is used for the prophylaxis of migraine but not for angina pectoris ? \nSelect and explain. \nA. Verapamil, B. Diltiazem, C. Flunarizine, D. Amlodipine', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]