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': 'A patient Shyam is admitted to the emergency following a drug overdosage with severe tachycardia. He had been receiving therapy for hypertension and angina. Which of the following drugs can cause tachycardia ? \nSelect and explain. \nA. Guanethidine, B. Isosorbide dinitrate, C. Propranolol, D. Verapamil', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]