Read the following passage: "The process of cellular respiration is how organisms convert glucose into energy (ATP). This complex process occurs in three main stages: glycolysis, the Krebs cycle (also known as the citric acid cycle), and oxidative phosphorylation. Glycolysis, the first stage, takes place in the cytoplasm and breaks down glucose into pyruvate, producing a small amount of ATP. The pyruvate then enters the mitochondria, where the Krebs cycle further breaks it down, releasing carbon dioxide and generating more ATP and electron carriers. Finally, oxidative phosphorylation, which includes the electron transport chain, occurs on the inner mitochondrial membrane, producing the vast majority of ATP through a series of redox reactions. This entire process is essential for sustaining life functions." Where does the majority of ATP production occur during cellular respiration?

1. ADuring oxidative phosphorylation in the mitochondria.
2. BDuring the initial breakdown of glucose.
3. CDuring the Krebs cycle in the mitochondria.
4. DDuring glycolysis in the cytoplasm.