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': 'Morphine ? \nSelect and explain. \nA. Stimulates CTZ zone of medulla, B. Stimulates respiratory centre of medulla, C. Depresses CTZ zone of medulla, D. None of the above', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Stimulates CTZ zone of medulla", 'role': 'assistant'}]