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': 'Buonian line is seen in chronic poisoning of: March 2004 \nSelect and explain. \nA. Arsenic, B. Lead, C. Copper, D. Mercury', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B i.e. Lead', 'role': 'assistant'}]