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: Physiology
[{'content': 'Hormonal vitamin is ? \nSelect and explain. \nA. Niacin, B. Pyridoxin, C. Vitamin D, D. Riboflavin', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Vitamin D Active form of vitamin D i.e. 1-25 dihydroxy-cholecalciferol is a vitamin produced in kidney.It acts on intranuclear receptors to regulate gene expressions (transcription factors).", 'role': 'assistant'}]