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: Biochemistry
[{'content': 'If starvation exceeds 7 days, the major nutritional supply of the brain comes from \nSelect and explain. \nA. Fatty acids, B. Ketone bodies, C. Protein breakdown, D. Carbohydrate breakdown', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]