Final answer:
Oxidative phosphorylation in the electron transport chain produces the most ATP in cellular respiration.
Step-by-step explanation:
The step of cellular respiration that produces the most ATP is oxidative phosphorylation, which occurs during the electron transport chain. In this stage, energy from NADH and FADH2, which are produced in glycolysis, the Krebs cycle, and the transformation of pyruvate, is transferred to ATP. Through a series of redox reactions, the electron transport chain generates a large amount of ATP. As many as 36 molecules of ATP can be produced from just one molecule of glucose in all three stages of aerobic cellular respiration combined.