Biology

The correct answer is: C.Cell Wall

Explanation:

The cell wall is a rigid layer that lies outside the cell membrane. It provides structural support, protection, and helps maintain the cell's shape. The cell wall is found in plant cells, fungi, bacteria, and some algae, but not in animal cells. In plants, it is mainly composed of cellulose.

Why the other options are incorrect:

A.Cytoskeleton: The cytoskeleton is an internal network of protein filaments that helps maintain the cell's shape and structure. It is inside the cell, not outside the membrane.