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': "'Red velvety' stomach mucosa is seen in poisoning with: Gujarat 07; JIPMER 14 \nSelect and explain. \nA. Mercury, B. Arsenic, C. Lead, D. Copper", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. Arsenic', 'role': 'assistant'}]