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: Physiology
[{'content': 'The neuromuscular transmitter released at neuromuscular junction is: \nSelect and explain. \nA. Dopamine, B. Epinephrine, C. Nor epinephrine, D. Acetylcholine', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]