This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: TCA Cycle, Subject name: Biochemistry
TCA cycle depends on availability of : 
Select and explain. 
A. Acetyl CoA, B. Oxaloacetate, C. Insulin, D. Glucagon
B: Oxaloacetate
Answer: B: Oxaloacetate 
Explanation: TCA cycle depends on availability of Oxaloacetate TCA cycle : Has no hormonal control. Vital cycle for the cells. Doesn't depend on insulin or glucagon. Depends on the availability of oxaloacetate. (not Acetyl CoA).