Answer:
Substrate.
Step-by-step explanation:
Enzyme is the bio catalyst that are used to increase the rate or speed of the biochemical reaction. Enzymes are made of proteins and are highly specific in nature.
The inhibitors may inhibit the activity of the enzyme. The inhibitors disrupt or may break the interaction between the substrate and the enzyme. They can compete with the substrate or may binds with the enzyme substrate complex and hinders the reaction.
Thus, the correct answer is substrate.