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': 'Chocolate or copper brown post moem staining is seen in all of the following causes of death, except: \nSelect and explain. \nA. Nitrates, B. Aniline dyes, C. Clostridium perfringence, D. Potassium chlorate', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Nitrates, Potassium chlorate, Potassium bicarbonate, Aniline, all produce chocolate or copper brown post-moem staining. Clostridium perfingence causes bronze pigmentation in septic aboion.', 'role': 'assistant'}]