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
The immediate precursor in the formation of acetoacetate from acetyl Co A in the liver is: 
Select and explain. 
A. Mevalonate, B. HMG CoA, C. Acetoacetyl CoA, D. 3-hydroxy-butyryl
B: HMG CoA
Answer: B: HMG CoA 
Explanation: B i.e. HMG CoA