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
Which of the following is primary ketone body? 
Select and explain. 
A. Acetone, B. Acetoacetate, C. Beta hydroxybutyrate, D. All of the above
B: Acetoacetate
Answer: B: Acetoacetate 
Explanation: Acetoacetate is the primary ketone body, secondary ketone bodies are acetone and beta hydroxybutyrate.