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': 'Brain is preserved in all of the following, except: AIIMS 06 \nSelect and explain. \nA. OPC poisoning, B. Alkaloid poisoning, C. Heavy metal poisoning, D. Volatile organic poisoning', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. Heavy metal poisoning', 'role': 'assistant'}]