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': 'Erethism occur in - \nSelect and explain. \nA. Hg, B. As, C. Pb, D. Cu', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Erethism is seen in mercury poisoning.', 'role': 'assistant'}]