You shove a chair with wheels(and let it go)and it starts moving across the floor. However, the chair soon shows down and comes to a complete stop. To keep the chair moving, you need to keep pushing on it. This simple experiment implies that ;

A) Newton's first law, or the law of inertia, does not apply to a chair moving horizontally
B) The action-reaction forces act on the chair and cancel each other
C) A net force in the direction opposite to the motion of the chair acts to slow it down
D) The weight of the chair slows it down