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: Pharmacology
[{'content': 'Losartan is:(2001) \nSelect and explain. \nA. ACE inhibitor, B. Angiotensin receptor blocker, C. Ca++ channel blocker, D. Ganglion blocker', 'role': 'user'}, {'content': 'Answer: B \nExplanation: b', 'role': 'assistant'}]