When an enzyme catalyzes a reaction:
a. substrate(s) bind in the active site
b. products bind in the active site
c. the shape of the enzyme remains unchanged
d. the enzyme is consumed by the reaction

Option A. "Substrate(s) bind in the active site.

Explanation:

Enzymes can be defined as biological catalysts, that enhances the rate of chemical or biochemical reaction.

Substrate binds to the enzyme on its active site and converts the substrate into a specific product.

Enzymes do not take part in the reaction but it lowers down its activation energy that accelerates the rate of reaction.

Thus, the correct answer is option A.

answer:

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