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': 'Which is not ketogenic? \nSelect and explain. \nA. Leucine, B. Lysine, C. Methionine, D. Tryptophan', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Methionine is purely glucogenic leucine is purely ketogenic others are both ketogenic & glucogenicRef: DM Vasudevan - Textbook of Biochemistry, 7th edition, page no: 27', 'role': 'assistant'}]