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': 'The major fuel for the brain after several weeks of starvation \nSelect and explain. \nA. Glucose, B. Fatty acid, C. Beta hydroxybutyrate, D. Glycerol', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The major fuel for brain in prolonged starvation is ketone bodies (Beta hydroxybutyrate, acetoacetate).', 'role': 'assistant'}]