Which sentence describes the shapes of substrates and the active sites of enzymes? A. They are both concave.
B. They are identical.
C. They are complementary.
D. They are both convex.

HELP

C. They are complementary

Explanation:

The active site is concave to accomodate the unusual shapes of the substrates, which are designed to fit solely in their designated active site. (This is the concept of specificity of reaction) Therefore, they complement each other.

they are both concave

Explanation:

they are both concave