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: A i.e. Hg (Mercury) Chronic mercury (Hg) poisoning presents with excessive salivationQ, diphtheria like membranous colitis dysentery and membranous glomerulonephritis, coarse tremors, insomnia, anorexia, PCT necrosisQ, Pink disease, erethism (i.e. disturbed personality in form of excrssive shyness & irritability) and mercuria lentis (i.e. brown spot on anterior capsule of lens)Q.', 'role': 'assistant'}]