In the eye, color vision is primarily affected by the presence of cones. Cones are specialized cells located in the retina, the back part of the eye. There are three types of cones, each sensitive to different colors of light - red, green, and blue. When light enters the eye and reaches the cones, they convert the different wavelengths of light into electrical signals that are sent to the brain. The brain then processes these signals to perceive color.

The choroid coat and sclerotic coat mentioned in options 1 and 2 are part of the outer layer of the eye called the sclera. They provide structural support and protection but do not directly affect color vision.

Rods mentioned in option 3 are another type of cells in the retina that contribute to vision in low light conditions but are not responsible for color perception.

Therefore, option 4, cones, is the correct answer.