This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vitamins and Minerals, Subject name: Biochemistry
[{'content': '1, 25 (OH)2 Cholecalciferol is formed in- \nSelect and explain. \nA. Skin, B. Liver, C. Spleen, D. Kidney', 'role': 'user'}, {'content': 'Answer: D \nExplanation: 25-hydroxy Cholecalciferol is formed in liver Whereas 1, 25 (OH)2 Cholecalciferol is formed in kidneys. Additional edge on synthesis of Vitamin D: Activation of 7-dehydro cholesterol by UV light in skin produces Cholecalciferol 25-hydroxylation in liver to form 25-hydroxy cholecalciferol 1-alpha- hydroxylation in kidneys to form 1,25 dihydroxy cholecalciferol PTH activates 1-alpha hydroxylase of kidneys', 'role': 'assistant'}]