In opponent-process theory, there are _____ primary colors.

• A. two
• B. four
• C. six
• D. ten

Answer: (B)

Verified step by step guidance

1. Understand the opponent-process theory, which is a color vision theory proposed by Ewald Hering.
2. Recognize that this theory suggests that our perception of color is controlled by three opposing systems: red-green, blue-yellow, and black-white.
3. Identify that each of these systems is made up of two opposing colors, which are considered primary in this context.
4. Count the primary colors involved in these opposing pairs: red, green, blue, and yellow.
5. Conclude that according to the opponent-process theory, there are four primary colors involved in color perception.