The difference in lipid and protein composition between the membranes of the endomembrane system is largely determined by A) the physical separation of most membranes from each other. B) the transportation of membrane lipids among the endomembrane system by small membrane vesicles. C) the function of the Golgi apparatus in sorting and directing membrane components. D) the modification of the membrane components once they reach their final destination. E) the synthesis of different lipids and proteins in each of the organelles of the endomembrane system.