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 one of the following drugs is most commonly employed in an attack of angina pectoris? \nSelect and explain. \nA. Sodium nitrate, B. Epinephrine, C. Nitroglycerina, D. Isosorbide dinitrate', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]