Five Billiard Balls Are in Contact and at Rest on a Wire

Multiple Choice

Five billiard balls are in contact and at rest on a wire that passes through their centers. Two billiard balls are slammed into one end of the row of five at a velocity . If the balls are free to slide but not roll and if the collision is elastic, which of the following is most likely to take place?

A) One ball at each end goes off with a speed v.
B) One ball on the side opposite the striking balls goes off with a speed of 2v.
C) The five balls move off together with a speed of 2v/5.
D) Two balls on the side opposite the striking balls go off with a speed of v.
E) None of these will occur.