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': 'Postmortem nasal swab in death following - \nSelect and explain. \nA. Cocaine poisoning, B. Hanging, C. Drowning, D. Strychnine poisoning', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Postmortem nasal swab is taken in poisoning with cocaine because cocaine is usually sniffed for its effects for addiction purposes. Long-term use of cocaine of sniffing causes ulceration and necrosis of the nasal septum.', 'role': 'assistant'}]