This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Death and postmortem changes, 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: Brain need not be preserved in heavy metal poisoning as it is not seen in brain tissue. Dr. Narayana Reddys Synopsis of Forensic Medicine & Toxicology 27 th edition pg. 62.', 'role': 'assistant'}]