Which molecule is generated when a fatty acid undergoes ß-oxidation?

When a fatty acid undergoes β-oxidation, it is broken down into two-carbon units that are released in the form of Acetyl-CoA. This process occurs in the mitochondria and involves a series of enzymatic reactions that systematically remove two carbon atoms from the fatty acid chain. Each cycle of β-oxidation results in the production of one molecule of Acetyl-CoA, which can then enter the citric acid cycle (Krebs cycle) for further energy production.

In addition to Acetyl-CoA, the process also generates reducing equivalents in the form of NADH and FADH2, which are important for ATP production in the electron transport chain. However, the direct product of β-oxidation that signifies the breakdown of the fatty acid into a usable form for energy metabolism is Acetyl-CoA. Therefore, Acetyl-CoA is the primary molecule generated when a fatty acid undergoes β-oxidation, making it the correct answer for this question.