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': 'Most commonly occurring amino acid in the collagen structure is \nSelect and explain. \nA. Serine, B. Glycine, C. Hydroxy proline, D. Proline', 'role': 'user'}, {'content': 'Answer: B \nExplanation: About 33%of aminoacids of collagen is glycine.Ref: DM Vasudevan - Textbook of Biochemistry, 7th edition, page no: 720', 'role': 'assistant'}]