Answer:
E
Step-by-step explanation:
A protein is made and inserted into the membrane of the rough endoplasmic reticulum. A binding site that is present in this protein is aligned so that it faces the lumen of the ER. If this protein is then moved to other endomembranes, the binding site is unlikely to be found at the cytosolic face of the plasma membrane whose main function is to protect the cell from its surroundings.