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: Biochemistry
[{'content': 'Pyruvate formation is associated with aminoacid \nSelect and explain. \nA. Alanine, glycine, histidine, proline, B. Alanine, glycine, methionine, cystidine, C. Phenylalanine, methionine, threonine, proline, D. Alanine, valine, isoleucine, leucine', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]