This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Galactose and fructose metabolism, Subject name: Biochemistry
The compound that regulates both glycolysis and gluconeogenesis is: 
Select and explain. 
A. Fructose-1,6-bisphosphate, B. Fructose-2,6-bisphosphate, C. Citrate, D. Glucose-6-phosphate
B: Fructose-2,6-bisphosphate
Answer: B: Fructose-2,6-bisphosphate 
Explanation: Fructose 2,6 bisphosphate Potent activator of PFK-1 inhibitor of gluconeogenic enzyme fructose 1,6 bisphosphatase. This helps in reciprocal regulation of glycolysis and gluconeogenesis.