Ewald Hering Proposed the Opponent-Process Theory of Color Vision Which

Ewald Hering proposed the opponent-process theory of color vision which claims:

A) Three types of color receptors are responsible for afterimages.
B) The four types of color receptors are sensitive to red, green, blue and the brightness of the light.
C) A red-green cone can transmit messages for red and green at the same time.
D) Staring at a green, black, and yellow flag for 30 seconds will not disturb the perception of color.