This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of protein and amino acid, Subject name: Biochemistry
[{'content': 'At which level does methionine enter the TCA cycle? \nSelect and explain. \nA. Acetyl co A, B. Succinyl co A, C. Oxaloacetate, D. Pyruvate', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Reference: Lehninger illustrated biochemistry 5th edition', 'role': 'assistant'}]