In what way do tight junctions influence the distribution of membrane proteins in epithelial cells?

• A. They restrict membrane proteins to either the apical or basal surface, maintaining cell polarity.
• B. They allow membrane proteins to freely move between the apical and basal surfaces.
• C. They facilitate the transport of membrane proteins to the extracellular matrix.
• D. They degrade membrane proteins that reach the basal surface.

Answer: (A)