The correct answer is option 2: Anaerobic Respiration.

Fermentation is a biological process that occurs in the absence of oxygen, which is known as anaerobic conditions. During fermentation, organic compounds such as glucose are broken down by microorganisms or cells to release energy in the form of ATP. This process is different from aerobic respiration (option 1) which requires oxygen.

Option 3, Exothermic Reaction, refers to a chemical reaction that releases heat. While fermentation does produce heat, it is not solely categorized as an exothermic reaction.

Option 4, Transpiration, is the process by which plants lose water vapor through their leaves. This process is unrelated to fermentation.

Therefore, option 2, Anaerobic Respiration, is the most accurate description of fermentation as it emphasizes the absence of oxygen during the process.