This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
[{'content': 'A male patient presents with headache , profuse sweating and palpitations with a blood pressure of 180/120 mmHg . The drug of choice would be \nSelect and explain. \nA. Nifedipine, B. Labetalol, C. Prazocin, D. Phenoxy benzamine', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ref Harrison 19 th ed pg 1627 Symptomatic hypeension with diastolic pressure of 120 suggests a diagnosis of hypeensive emergency . Labetalol (IV) is the drug of choice for management of hypeensive emergency.', 'role': 'assistant'}]