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: Forensic Medicine
[{'content': 'Fatal dose morphine is: BHU 12 \nSelect and explain. \nA. 100 mg, B. 200 mg, C. 300 mg, D. 500 mg', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. 200 mg', 'role': 'assistant'}]