Johnny, a Living Environment student, has a homework assignment where he must come up with an real-world analogy for the cell wall. Johnny decides that he will compare the cell wall to a doorman because a doorman only allows certain people into a building, just like a cell wall only lets certain materials into the cell. What error did Johnny make in his analogy?

A.
Instead of cell wall, he should have said cell membrane because it is selectively permeable.
B.
Instead of cell wall, he should have said the nucleus because the nucleus decides what enters and exits the cell.
C.
His analogy between the doorman and the cell wall was correct, but the cell wall doesn't allow any materials pass through into the cell.
D.
Johnny did not make an error.