Here's why:
* Glycolysis is the breakdown of glucose into pyruvate. This process occurs in the cytoplasm and does not require oxygen. It is the first stage of cellular respiration, but it can also operate independently as a way for cells to generate a small amount of ATP even when oxygen is limited.
Let's look at other processes:
* Krebs cycle (Citric Acid Cycle) and Electron Transport Chain (ETC) are both parts of aerobic respiration and require oxygen to function effectively.
* Photosynthesis is a process that occurs in plants and other photosynthetic organisms and uses sunlight, water, and carbon dioxide to produce glucose and oxygen. It requires light and is not a process in eukaryotic cells.
Therefore, glycolysis is the only process listed that proceeds normally whether oxygen is present or absent.
