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': 'Preservation of brain is not required in \nSelect and explain. \nA. Alkaloid poisoning, B. Organophosphorus poisoning, C. Volatile organic poisoning, D. Heavy metal poisoning', 'role': 'user'}, {'content': 'Answer: D \nExplanation: D i.e. Heavy metal', 'role': 'assistant'}]