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': 'All of the following are required for hydroxylation of proline in collagen synthesis except - \nSelect and explain. \nA. O2, B. Vitamin C, C. Dioxygenases, D. Pyridoxal phosphate', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Hydroxylation of proline and lysine during collagen synthesis requires vitamin C (ascorbic acid), molecular oxygen (O2), α-ketoglutarate and enzymes dioxygenases (prolyl hydroxylase, lysyl hydroxylase).', 'role': 'assistant'}]