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: Pharmacology
[{'content': 'In drug metabolism, hepatic cytochrome P–450 system is responsible for: \nSelect and explain. \nA. Phase I reactions (hydrolysis, oxidation, reduction etc.) only, B. Phase II reactions (conjugation, synthesis etc.) only, C. Both phase I and II reactions, D. Converting hydrophilic metabolites to lipophilic metabolites', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]