Answer: option D
Step-by-step explanation:
Although they can be in constant lateral motion. The lipid bilayer membrane is so organized in the sense that the hydrophilic heads which might contain some polar or molecules that can mix with water faces both the cytosol and the outer environment while the hydrophobic tails of both layers that are entirely insoluble in water faces one another thus forming a core that repels mixing. This it is very rare for the possibilities molecules to flip.