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': 'Calcitonin causes hypocalcemia by: \nSelect and explain. \nA. Inhibiting bone resorption, B. Promoting osteolysis, C. Decreasing renal tubular reabsorption of calcium, D. Decreasing absorption of phosphorus', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]