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': 'The brick red colour of postmortem lividity is deen in poisoning due to \nSelect and explain. \nA. Carbonmonoxide, B. Hydrogen sulfide, C. Phosphorous, D. Cyanide', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]