Which is true about the chemical composition of cell membranes? ( )
选项：

A:Lipid anchoring protein is located only on the outer surface of the plasma membrane.
B:The transmembrane region of internal membrane protein is mostly composed of hydrophilic amino acids.
C:Glycolipids and glycoproteins are located on both sides of the lipid layer and are related to cell recognition and signal transduction.
D:Phospholipids, cholesterol and glycolipid are molecules for cell membrane.