After You Have Watched the Falling of the Water in a Waterfall

Multiple Choice

After you have watched the falling of the water in a waterfall for about a minute, if you look at a blank surface, such as a white wall, you will get a sense of ______.

A) motion going upward, in the opposite direction of the falling water
B) motion going downward, in the same direction as the falling water
C) akinetopsia, seeing movement upward as separate images
D) akinetopsia, seeing movement downward as blurred images