Question

what is the main function of the cell membrane in an animal cell?
to make proteins
to control which substances enter and leave the cell
to contain the information that the cell uses for growth and activities
to break down waste and worn - out cell parts

Explanation:

The cell membrane in an animal cell functions as a selectively permeable barrier. It regulates the movement of substances (like nutrients, ions, and waste) into and out of the cell. Let's analyze the options: "to make proteins" is the role of ribosomes. "to contain the information..." is for the nucleus. "to break down waste..." is for lysosomes. So the correct function matching the cell membrane is controlling substance entry/exit.

Answer:

to control which substances enter and leave the cell