The correct answer is option B. "It is unchanged and can be used again for the same chemical reaction".
Explanation:
One characteristic of enzymes is that they are reusable. Enzymes are not reactants and are not used in the reaction that they catalyze. Once the enzyme catalyzes a chemical reaction, it remains unchanged and can be used again for the same chemical reaction. Usually, one enzyme can bind onto several substrate molecules and catalyze the same reaction multiple times.
