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': 'Mechanism of cyanide poisoning is by inhibiting- \nSelect and explain. \nA. DNA synthesis, B. Cytochrome oxidase, C. Protein breakdown, D. Protein synthesis', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]