Consider a System Containing Three Objects That Move with Different

Multiple Choice

Consider a system containing three objects that move with different velocities. The objects can interact with each other through forces. In this system

A) the total kinetic energy of the objects will not change unless an outside force is applied.
B) the objects can only collide if an outside force is applied.
C) any collisions between the objects must be elastic.
D) the total momentum of the objects cannot change unless an outside force acts on the system.