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': 'All are ketogenic & glucogenic amino acids except \nSelect and explain. \nA. Tyrosine, B. Isoleucine, C. Phenyalanine, D. Serine', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Serine is a glucogenic amino acid.Ref: DM Vasudevan - Textbook of Biochemistry, 7th edition, page no: 245.fig 18.16.', 'role': 'assistant'}]