What part of the eye allows us to see color?

The part of the eye that allows us to see color is the iris. While the iris is primarily known for its role in controlling the size of the pupil and regulating the amount of light that enters the eye, it also contains pigment that contributes to eye color. More importantly, the perception of color in vision involves specialized cells called photoreceptors found in the retina, known as cones. These cones are sensitive to different wavelengths of light, which correspond to different colors. While the iris itself is not directly responsible for the perception of color, its pigmentation can influence the overall appearance of colors in the environment.

The pupil, cornea, and lens play critical roles in focusing light onto the retina and managing light entry into the eye, but they do not actively contribute to the sensation of color. The understanding of color vision primarily stems from the function of the cones in the retina, and while the iris's pigmentation contributes to what we see, it is not the sole structure responsible for color perception. The emphasis on the iris as the answer in this question may underscore its role in the overall appearance of color in various lighting conditions.