While each of these processes are believed to have evolved prior to aerobic respiration,which one is the most critical process,without which aerobic respiration could never have developed?

Question

Quizplus · Accepted Answer

Aerobic respiration requires oxygen as the final electron acceptor in the electron transport chain to produce ATP. Oxygenic photosynthesis is the process that represents the origin of oxygen in the Earth's atmosphere, which eventually allowed for the development of aerobic respiration. Anoxygenic photosynthesis, alcohol fermentation, and lactic acid fermentation do not provide the necessary oxygen for aerobic respiration.

While Each of These Processes Are Believed to Have Evolved