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': 'Bright red color on postmortem staining found in – \nSelect and explain. \nA. CO, B. P, C. H2S, D. HCN', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The colour of postmortem hypostasis in HCN poisoning is bright red due to impaired oxygenation of tissues and formation of cyanmethhemoglobin.', 'role': 'assistant'}]