This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Death and postmortem changes, Subject name: Forensic Medicine
[{'content': 'Bright red color on postmoem staining found in - \nSelect and explain. \nA. CO, B. HCN, C. H2S, D. P', 'role': 'user'}, {'content': 'Answer: B \nExplanation: The colour of postmoem hypostasis in HCN poisoning is bright red due to impaired oxygenation of tissues and formation of cyanmethhemoglobin. Dr.Narayana Reddys Synopsis of Forensic Medicine and Toxicology 27th edition pg. 78,315.', 'role': 'assistant'}]