Here's why:

* Electron Transport Chain: The inner mitochondrial membrane houses the electron transport chain (ETC). This chain consists of a series of protein complexes that pass electrons down a gradient, releasing energy to pump protons across the membrane.

* Cytochrome c Oxidase (Complex IV): This enzyme is the final complex in the ETC. It receives electrons from cytochrome c and uses them to reduce molecular oxygen (O2) to water (H2O). This is the crucial step where oxygen is consumed during cellular respiration.

In summary: Cytochrome c oxidase is the only enzyme directly embedded in the inner membrane transport chain and plays a vital role in the final step of electron transport and oxygen consumption.