What best explains the observation of an enzyme being selective in the reaction it catalyzes?
a. reaction-specific enzymes assume a fit by folding around the most numerous substrate molecules.
b. molecules and active sites vary in size; only properly sized molecules can fit.
c. there is a precise compatibility between an enzyme's active site and the substrate molecule.
d. specificity refers to the action of the enzyme, such as hydrolysis, and relatively few molecules can be hydrolyzed.
e. active sites carry slight negative charges, while substrates tend to carry slight positive charges.