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
Which of the following receptors is activated by acetylcholine and blocked by atropine. 
Select and explain. 
A. Nicotinic, B. Muscarinic, C. Alpha 1 and 2, D. Beta 1 and 2
B: Muscarinic
Answer: B: Muscarinic 
Explanation: None