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': 'Hea at rest utilises: \nSelect and explain. \nA. Fatty acids, B. Ketone bodies, C. Glucose, D. Any of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Fatty acids', 'role': 'assistant'}]