Final answer:
The best description of cellular respiration in the mitochondria is the generation of ATP through the oxidation of organic molecules, involving glycolysis, the Krebs cycle, and oxidative phosphorylation.
Step-by-step explanation:
The phrase that best describes cellular respiration in the mitochondria is D) Generation of ATP through the oxidation of organic molecules. Cellular respiration involves a series of metabolic pathways that convert glucose into ATP, the energy currency of the cell. Glycolysis starts the process in the cytoplasm, splitting glucose into pyruvate, generating a small amount of ATP and the electron carrier NADH. The Krebs cycle, which occurs in the mitochondrial matrix, further oxidizes the pyruvate, contributing to more NADH production as well as FADH2 and some ATP. The majority of ATP, however, is produced through oxidative phosphorylation, a process happening in the inner mitochondrial membrane where the energy from NADH and FADH2 is used to create a proton gradient that drives the synthesis of ATP from ADP by the enzyme ATP synthase, with oxygen required as the final electron acceptor.