An inability to form which of the following would prevent aerobic respiration from occurring?

A. Pyruvate

B. Oxygen

C. Carbon dioxide

D. ATP

The answer is B. Oxygen

To do aerobic respiration, oxygen is needed. Without oxygen, the body won't produce some substance which will be needed to do Krebs cycle and electron transport. Most of the energy will be produced by the electron transport so without oxygen the amount of energy produced will be much less.