This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of carbohydrate, Subject name: Biochemistry
The activity of pyruvate carboxylase is dependent upon the positive allosteric effector 
Select and explain. 
A. Succinate, B. AMP, C. Isocitrate, D. Acetyl Co A
D: Acetyl Co A
Answer: D: Acetyl Co A 
Explanation: Pyruvate carboxylase is an allosteric enzyme. Acetyl CoA is an activator of pyruvate carboxylase so the generation of oxaloacetate is ored when acetyl CoA level is sufficiently high.Ref: DM Vasudevan, 7th edition, page no: 120