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': 'In a completely charred body at autopsy, medical officer can say that the burns are antemoem if he can find : \nSelect and explain. \nA. Soot in respiratory passage, B. Cyanosis of finger nails, C. Congestion of kidney, D. Pale internal organs', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e. Soot in respiratory passage', 'role': 'assistant'}]