Which Statement About the Feedback Inhibition of Enzymes Is Not

Which statement about the feedback inhibition of enzymes is not true?

A) It is usually exerted through allosteric effects.
B) It is directed at the enzyme that catalyzes the commitment step in a metabolic pathway.
C) It affects the rate of reaction, not the concentration of enzyme.
D) It acts by permanently modifying the active site.
E) It is an example of reversible inhibition.