Final answer:
In a fasted state, ACC1 is inhibited to decrease fatty acid synthesis, and ACC2 is active to promote fatty acid oxidation for energy production. The correct answer is b) ACC2.
Step-by-step explanation:
In the context of a fasted state, the activity of enzymes related to fatty acid metabolism is regulated to manage energy resources efficiently. Acetyl-CoA carboxylase 1 (ACC1) and Acetyl-CoA carboxylase 2 (ACC2) play pivotal roles in lipid metabolism. ACC1 is mainly involved in fatty acid synthesis whereas ACC2 is associated with fatty acid oxidation.
During fasting, the body prioritizes fatty acid oxidation to produce energy because glucose levels are low. The enzyme ACC2 becomes inhibited in order to allow the transport of fatty acids into the mitochondria for oxidation, which is facilitated by the activation of CPT1 (carnitine palmitoyltransferase I). Therefore, the correct answer is: b) ACC2 as it is the form that remains active implying that ACC1 is inhibited to decrease fatty acid synthesis.