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': 'Nails and hairs are commonly preserved in: \nSelect and explain. \nA. Acute lead poisoning, B. Acute arsenic poisoning, C. Chronic arsenic poisoning, D. All of the above', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Chronic arsenic poisoning', 'role': 'assistant'}]