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: Unknown
Which of the following is not a ketone body -(PGI 84) 
Select and explain. 
A. Acetone, B. Acetic acid, C. Acetoacetate, D. Beta-hydroxybutyric acid
B: Acetic acid
Answer: B: Acetic acid 
Explanation: Ketone bodies are three water - soluble molecules (acetoacetate, beta-hydroxybutyrate, and their spontaneous breakdown product, acetone) that are produced by the liver from fatty acids. Acetoacetic acid is a ketone body, but acetic acid is not. Note that acetic acid is hydrophobic while acetoacetate is water-soluble.