Which of the Following Statements Regarding the Structure and Function

Which of the following statements regarding the structure and function of cell membranes is correct?

A) The phospholipid bilayer is arranged so that the hydrophilic heads of the phospholipid molecule face the extra- and intracellular fluids.
B) Some proteins integrated into the membrane serve as channels for the passage of nonpolar molecules through the membrane.
C) Peripheral membrane proteins function as channels associated with transport of ions through the membrane.
D) Cholesterol molecules function to transport ions from one side of the plasma membrane to the other.
E) The plasma membrane is a layer of phospholipid molecules with their hyrophilic head groups in contact with the extracellular solution and the hydrophobic tail groups in contact with the intracellular solution.