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: Physiology
[{'content': 'Alpha-methyldopa is primarily used for \nSelect and explain. \nA. Pregnancy induced hypeension, B. Renovascular hypeension, C. First line agent in hypeension, D. Refractory hypeension', 'role': 'user'}, {'content': 'Answer: A \nExplanation: They act on central alpha 2a receptors to decrease efferent sympathetic activity. It decreases t.p.r more than H.R or C.O It is infrequently used now. (Ref: Essentials of medical pharmacology, K.D Tripathi, 7th edition, page 566)', 'role': 'assistant'}]