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: Social & Preventive Medicine
[{'content': 'Iron requirement in pregnancy – \nSelect and explain. \nA. 1000 mg, B. 35 mg, C. 500 mg, D. 800 mg', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]