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
Acetyl CoA carboxylase is activated by 
Select and explain. 
A. Malonyl CoA, B. Citrate, C. Palmitoyl CoA, D. Acetoacetate
B: Citrate
Answer: B: Citrate 
Explanation: Citrate

Acetyl-CoA carboxylase is an allosteric enzyme, it is activated by citrate and inhibited by long-chain acyl-CoA (palmitoyl CoA).