Which statement about the cell membrane is true?
a)it contains cellulose and sugars that are involved in communication.
it is present in animal cells only.
it is rigid and elastic for supporting the cell’s shape.
it prevents harmful substances from entering a cell.

whoever answers it i say you! : )

D. It prevents harmful substances from entering the cell. I am very confident in this answer. The cell membrane is selectively permeable, and its job is to let certain things in and to keep certain things out.

you must remain stopped until the stop signal is retracted and the red lights are turned off. approaching traffic in the opposite roadway of a divided highway shall not be required to stop, even if the school bus has the stop-arm extended and the alternately flashing warning signal lamps on.