22. Which of the following statements regarding allosteric regulation of enzymes is correct? I.Allosteric enzymes often exhibit sigmoidal (cooperative) kinetics rather than hyperbolic Michaelis- Menten kinetics. II. The R-state of an allosteric enzyme has a lower affinity for the substrate than the T-state. III. Feedback inhibition of a metabolic pathway often involves allosteric regulation of the first committed enzyme. (A) I and II (B) II and III (C) I and III (D) I only (E) All of them are correct.