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': 'Arsenic causes all, except: WB 09 \nSelect and explain. \nA. Raindrop pigmentation, B. Alopecia, C. Palmar hyperkeratosis, D. Blue line in gums', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. Blue line in gums', 'role': 'assistant'}]