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': '25-Dihydroxycholecalciferol is converted to 1,25-dihydroxycholecalciferol in: \nSelect and explain. \nA. Skin, B. Lung, C. Liver, D. Kidney', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]