Problem 8-34 Elastic collision

A superball of mass $22\; g$ rolls with a speed of $3.5\; m/s$ toward another (stationary) superball of mass $27\; g$. If the balls have a head-on elastic collision, what are the velocities magnitudes and directions) of the balls after the collision?
[Ans. $3.1\; m/s$ forward and $0.4\; m/s$ backward]

As is the case with all problems in Physics, it is a good idea to make a drawing of the situation. For collisions the drawing should include the conditions before and after. Which drawing below is best?

(A)

(B)

(C)