Which of the following statements regarding the movement of molecules across cell membranes is true?
A)In facilitated diffusion, a molecule is moved across a membrane against its
concentration gradient

B)Water molecules are commonly actively transported out of cells.

C)Three examples of passive transport are diffusion, facilitated diffusion, and osmosis.

D)Polar molecules generally diffuse more readily through the plasma membrane than do
nonpolar molecules of the same size.