Which of the following is a product of glycolysis?

Glycolysis is a metabolic pathway that breaks down glucose into pyruvate, which is a key step in cellular respiration. During glycolysis, one molecule of glucose (a six-carbon sugar) is converted into two molecules of pyruvate (which contain three carbons each). This process occurs in the cytoplasm of the cell and does not require oxygen.

In addition to producing pyruvate, glycolysis generates a net gain of two molecules of ATP and two molecules of NADH (not NADPH). The production of pyruvate is crucial because it can then be utilized in further metabolic processes, either entering aerobic respiration in the presence of oxygen or undergoing fermentation in the absence of oxygen.

The other options listed do not represent products of glycolysis: oxygen is not produced in this pathway, glucose is the substrate that is being broken down, and NADPH is primarily produced through the pentose phosphate pathway, not glycolysis. Therefore, the product of glycolysis, specifically the formation of 3-carbon pyruvate, is correctly identified as the right answer.