Answer:
The correct answer is B. pyruvate
Step-by-step explanation:
In glycolysis, glucose is oxidized to produce 2 molecules of NADH, ATP, and pyruvate. Then this pyruvate molecule is used in the Kreb cycle and gets fully oxidized into carbon dioxide and water.
This oxidation of pyruvate molecule gives rise to more NADH and FADH₂ molecule. These molecules are reduced form of energy which is used as a source of electron during oxidative phosphorylation to produce more ATP molecules.
Therefore pyruvate is the useful product of glycolysis which is utilized to give energy to the cell in the form of ATP.