If a Flatworm Is Positioned Relative to a Stationary Light

If a flatworm is positioned relative to a stationary light source such that more light-sensitive cells are stimulated in its right than in its left eye cup, the planarian will

A) turn to the left.
B) turn to the right.
C) make a complete clockwise circle.
D) make a complete counterclockwise circle.
E) stop moving.