This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Adrenergic System, Subject name: Pharmacology
[{'content': 'Propranolol can be used in all of the following conditions except \nSelect and explain. \nA. Thyrotoxicosis, B. Variant angina, C. Migraine, D. Hypertension', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (B) Variant angina(Ref: KDT 8th/e p161)Propranolol worsens variant angina, due to unopposed a receptor mediated coronary constriction.For indications of b -blockers, refer to text.', 'role': 'assistant'}]