Answer:
A
Step-by-step explanation:
Enzymes are specific biological catalysts, that can speed up reactions by lowering the overall activation energy required for the reaction.
There are many different enzymes, and each one is specific to one reaction.
Example: Lactase, is an enzyme that is required in the breaking down of lactose (the sugar found in milk), and lactase cannot catalyse a reaction for the breakdown of starch.