Final answer:
The outer membrane of an RBC consists of phospholipids, glycoproteins, and cholesterol.
Step-by-step explanation:
The outer membrane of a red blood cell (RBC) consists of phospholipids, glycoproteins, and cholesterol. Phospholipids form the bilayer of the membrane, providing structure and serving as a barrier. Glycoproteins are involved in cell adhesion and recognition, while cholesterol is integral to the plasma membrane, helping to maintain fluidity and stability.