As Part of an Experiment, Billy Is Sitting in a Darkened

Multiple Choice

As part of an experiment, Billy is sitting in a darkened room. A light is flashed on a certain point in the room, then flashed off, and a second light is flashed on a split second later at a point a short distance away. This process is repeated several times. Although Billy is really seeing two separate lights flashed at different points on the wall, he perceives them as one light moving from one point to another. This is an example of ________.

A) the phi phenomenon
B) convergence
C) stroboscopic motion
D) the autokinetic illusion