With a Point-Light Walker Display, a Viewer Can Distinguish a Runner

With a point-light walker display, a viewer can distinguish a runner from a dancer or a person walking on a sidewalk from one on a trampoline, and accurately perceive the display:

A) with fewer light points.
B) with light points that are located on the torso only.
C) when the timing of the movement of light points is not coordinated.
D) when light points are placed on the joints.