Which of the following statement is true? a. The active site is only a small part of the total enzyme volume.
b. The active site of an enzyme is the region of an enzyme where substrate molecules bind and undergo a chemical reaction.
c. According to Kosland's induced fit theory, the active site is inflexible and cannot change shape during the catalytic process.
d. An active site can catalyze a reaction repeatedly as the amino acid residues involved in the catalytic process are not altered at the end of the enzymatic reaction.
e. When an enzyme's substrate binds the active site, water usually exists the site for catalysis to occur.