How Do Trichromatic and Opponent-Process Theories Differ

How do trichromatic and opponent-process theories differ?

A) In opponent-process theory, the cells responsive to color operate in conjunction rather than independently.
B) In opponent-process theory, the cells responsive to color operate independently rather than in conjunction.
C) Opponent-process theory suggests that there are three, rather than four, primary colors.
D) Trichromatic theory offers a better explanation of the perception of afterimages.