How Does a Noncompetitive Inhibitor Decrease the Rate of an Enzyme-Catalysed

Multiple Choice

How does a noncompetitive inhibitor decrease the rate of an enzyme-catalysed reaction?

A) by binding to the active site of the enzyme, thus preventing binding of the normal substrate
B) by binding to an allosteric site, thus changing the shape of the active site of the enzyme
C) by decreasing the free-energy change of the reaction catalysed by the enzyme
D) by binding to the substrate, thus changing its shape so that it no longer binds to the active site of the enzyme