Question

recognition proteins, such as those embedded on the surface of red blood cells, are composed of
nucleic acids.
phospholipases.
steroids.
glycoproteins.

Explanation:

Glycoproteins are proteins with carbohydrate chains attached. They play important roles in cell - cell recognition. Nucleic acids (like DNA and RNA) store genetic information. Phospholipases are enzymes that act on phospholipids. Steroids are a type of lipid with a four - ring structure. Since recognition proteins on red blood cells need to interact with other cells (a function related to the carbohydrate - protein complex), glycoproteins are the correct answer.

Answer:

glycoproteins.