4. How does inhibition of an enzyme-catalyzed reaction by a competitive inhibitor differ from inhibition by a noncompetitiveinhibitor?
(A) Competitive inhibitors interfere with the enzyme； noncompetitive inhibitors interfere with the reactants.
(B) Competitive inhibitors bind to the enzyme reversibly； noncompetitive inhibitors bind to it irreversibly.
(C) Competitive inhibitors change the enzyme's tertiary structure； noncompetitive inhibitors cause polypeptide subunits todissociate.
(D) Competitive inhibitors bind to the active site of the enzyme； noncompetitive inhibitors bind to a different site.
(E) Noncompetitive inhibitors bind to the active site of the enzyme； competitive inhibitors bind to a different site.