Under Which of the Following Conditions Can a Ladder Standing

Multiple Choice

Under which of the following conditions can a ladder standing on a frictionless horizontal floor and leaning against a rough vertical wall be in equilibrium?

A) The normal force exerted by the floor on the ladder equals the normal force the wall exerts on the ladder.
B) The weight of the ladder is equal in magnitude to the frictional force the wall exerts on the ladder.
C) A ladder in this situation cannot be in equilibrium.
D) The normal force exerted by the floor on the ladder equals the weight of the ladder.
E) The normal force exerted by the floor on the ladder equals the frictional force the wall exerts on the ladder.