This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Beta oxidation of fatty acids, Subject name: Biochemistry
[{'content': "Ketone body that cannot be detected by Rothera's test: \nSelect and explain. \nA. Acetoacetate, B. Acetone, C. Beta hydroxy butyrate, D. All the above can be detected", 'role': 'user'}, {'content': "Answer: C \nExplanation: Rothera's test can only detect acetoacetate and acetone, and not beta-hydroxy butyrate. Rothera's test: Ketone bodies react with sodium nitroprusside (in the presence of NH3) to form a purple colored ring. Positive test indicate Acetoacetate and Acetone. No specific test available for beta-hydroxy butyrate. So, it is first oxidised to Acetoacetate, then Rothera's test is performed.", 'role': 'assistant'}]