According to the induced fit hypothesis of enzyme catalysis, which if the following is correct?
a. the binding of the substrate depends on the shape of the active site
b. some enzymes change their structure when activators bind to the enzyme
c. a competitive inhibitor can outcompete the substrate for the active site
d. the binding of the substrate changes the shape of the enzyme's active site
e. the active site creates a microenvironment ideal for the reaction

the binding of the substrate changes the shape of the enzyme's active site

Explanation:

According to induced fit theory, binding of substrate to the active site of the enzyme causes a conformational change in enzyme. This is referred to as the induced-fit mechanism and was postulated by Daniel Koshland in 1958. The induced fit brings specific functional groups on the active site of the enzyme into the proper position to catalyze the reaction and thereby enhances the catalytic activity of the enzyme. The induced conformational change facilitates the formation of additional weak interactions in the transition state.

carbohydrates are the body's preferred source of energy.

a "theory" a suggestion that is not 100 % accurate, or a figure. some people say its a theory because they of all the passed theory's about one subject. it depends sometimes theory might be accurate and sometimes they are.