This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Physiology
[{'content': 'Calcium absorption from gut is enhanced by \nSelect and explain. \nA. Parathyroid hormone, B. Calcitonin, C. 1,25 dihydroxy cholecalciferol, D. All', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Calcitriol -1,25-dihydroxycholecalciferol; a form of vitamin D used as a calcium regulator in the management of hypocalcemia in conditions such as rickets, osteodystrophy, hypoparathyroidism, and complications of renal dialysis; administered orally or intravenously.Ref: Ganong&;s review of medical physiology; 24th edition; page no:-377', 'role': 'assistant'}]