Physics - web assign visual problem?

A hard rubber ball, not affected by air resistance in its motion, is tossed upward from shoulder height, falls to the sidewalk, rebounds to a somewhat smaller maximum height, and is caught on its way down again. This motion is represented in the figure below, where the successive positions of the ball circle a through circle g are not equally spaced in time. At point circle e the center of the ball is at its lowest point in the motion. The motion of the ball is along a straight line, but the diagram shows successive positions offset to the right to avoid overlapping. Consider the positive y direction to be upward.

In each ranking below, remember that zero is greater than a negative value. Use a for circle a, b for circle b, etc. Use only ">" or "=" symbols. If any elements are equal, show their equality in alphabetic order (for example: a>b=c).

http://img115.imageshack.us/img115/4725/cq213zz5.g...

(a) Rank the situations circle a through circle g according to the speed of the ball |vy| at each point, with the largest speed first.

correct check mark

(b) Rank the same situations according to the velocity of the ball at each point.

correct check mark

(c) Rank the same situations according to the acceleration ay of the ball at each point.

A) d>f>a=c>g>b=e

f>a>g>b=e>c>d

C) ......

I need help with C

i thought acceleration would be constant throughout; but its not ...

any suggestions?