This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nutrition and health, Subject name: Social & Preventive Medicine
[{'content': 'All of the following are required more during lactation as compared to pregnancy, except - \nSelect and explain. \nA. Iron, B. Vitamin A, C. Niacin, D. Energy', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ref: Park 25th edition Pgno : 674', 'role': 'assistant'}]