Question

in the image above the object labeled b is which of the following?
active site
enzyme substrate complex
enzyme
substrate

Explanation:

In enzyme - substrate interactions, the active site is the region on the enzyme (labeled C) where the substrate (labeled A) binds. The enzyme - substrate complex would be the combination of the enzyme and substrate. The substrate is the molecule that the enzyme acts upon. The active site is the specific part of the enzyme that fits the substrate, as depicted in the diagram for label B.

Answer:

active site