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
Inhibition of glycogenolysis and gluconeogenesis is caused by 
Select and explain. 
A. Insulin, B. Glucogon, C. Glucocoicoid, D. Epinephrine
A: Insulin
Answer: A: Insulin 
Explanation: Insulin, a key inhibitor of hepatic glucose production, has effects on both glycogenolysis and gluconeogenesisRef: DM Vasudevan, 7th edition