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': 'Which of the follow is a "somniferous toxin" ? \nSelect and explain. \nA. Dhatura, B. Opium, C. Belladonna, D. Cannabis', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]