Which of the Following Statements Concerning Lipid Bilayers Is Correct

Which of the following statements concerning lipid bilayers is correct?

A) Both the exterior and interior surface of a lipid bilayer contain groups that are nonpolar.
B) The interior of a lipid bilayer is polar.
C) The two layers of molecules in a lipid bilayer are present in a "tail-to-tail" arrangement.
D) More than one correct response.
E) No correct response.