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': 'The primary effect of calcitonin is: \nSelect and explain. \nA. Bone deposition, B. Bone resorption, C. Increases intestinal absorption of calcium, D. Decreases intestinal absorption of calcium', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]