This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular system, Subject name: Pharmacology
[{'content': 'The drug contraindicated in variant angina is \nSelect and explain. \nA. Aspirin, B. GTN, C. Propranolol, D. Nicorandil', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Beta blockers are contraindicated invariant or vasospastic angina as they produce vasoconstriction by blocking beta 2 receptors which produce vasodilatation Also, the unopposed action of alpha receptor activation can l.t vasoconstriction. Ref: Katzung 13th ed Pg: 203-206', 'role': 'assistant'}]