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': 'Increased calories required during pregnancy : \nSelect and explain. \nA. 300, B. 550, C. 800, D. 400', 'role': 'user'}, {'content': 'Answer: A \nExplanation: 300', 'role': 'assistant'}]