Which is present in every bacterium?

Explanation

Correct option is C cell membrane, The cell membrane, also known as the plasma membrane, is a semipermeable barrier that surrounds the cytoplasm of bacterial cells. It consists of a lipid bilayer with embedded proteins. The cell membrane is crucial for regulating the movement of substances in and out of the cell, maintaining the cell's internal environment, and providing structural support. It also plays a role in communication and signal transduction.