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: Gynaecology & Obstetrics
[{'content': 'Calcium requirement per day during the third trimester of pregnancy : \nSelect and explain. \nA. 20 mg, B. 100 mg, C. 750 mg, D. 1000 mg', 'role': 'user'}, {'content': 'Answer: D \nExplanation: 1000 mg', 'role': 'assistant'}]