In the presence of oxygen, all cells synthesize ATP via the process of glycolysis. Many cells also can metabolize pyruvate if oxygen is not present, via the process of --

The option are not given, here are the options gotten from another website.

A. Aerobic respiration

B. Electron Transport Chain

C. Anaerobic respiration

D. Krebs cycle

The correct option is C.

Explanation:

This is because anaerobic respiration is a type of respiration that produced ATP. pyruvate are metabolize in the absence of oxygen by a process called fermentation and fermentation us anaerobic respiration. And fermentation is the chemical process where glucose or substrates are broken down in the absence of oxygen by the activities of enzymes. When pyruvate are metabolize in the absence of oxygen , it will produce lactate.

answerbloodstream;