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
Which of the following enzymes found in the liver is involved in gluconeogenesis during the postabsorptive state? 
Select and explain. 
A. Glucose-6-phosphate dehydrogenase, B. 6-phosphogluconate dehydrogenase, C. Glucose-6-phosphatase, D. Glucokinase
C: Glucose-6-phosphatase
Answer: C: Glucose-6-phosphatase 
Explanation: Glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase are irreversible enzymes in the pentose phosphate pathway. Glucokinase is involved with phosphorylation of glucose when hepatic concentrations of glucose are high. Glucose-6-phosphatase hydrolyzes glucose-6-phosphate to form free glucose as the final step in gluconeogenesis.