Two Objects of Equal Mass Traveling Toward Each Other with Equal

Multiple Choice

Two objects of equal mass traveling toward each other with equal speeds undergo a head on collision. Which one of the following statements concerning their velocities after the collision is necessarily true?

A) They will exchange velocities.
B) Their velocities will be reduced.
C) Their velocities will be unchanged.
D) Their velocities will be zero.
E) Their velocities may be zero.