Question

what is the main function of the cell membrane in a plant cell?
to give the cell its fixed shape
to control which substances enter and leave the cell
to make proteins
to contain the information that the cell uses for growth and activities

Explanation:

The cell - membrane is a selectively permeable barrier. It controls the movement of substances like ions, nutrients, and waste products in and out of the cell. The cell wall gives a plant cell its fixed shape, ribosomes make proteins, and DNA in the nucleus contains growth - related information.

Answer:

to control which substances enter and leave the cell