This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
[{'content': 'Which of the following receptors is activated by acetylcholine and blocked by atropine. \nSelect and explain. \nA. Nicotinic, B. Muscarinic, C. Alpha 1 and 2, D. Beta 1 and 2', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]