Final answer:
The question is about the cones and rods, which are the photoreceptors in the eye. Option D is correct.
Step-by-step explanation:
The question refers to the photoreceptors in the human eye, specifically rods and cones. The cones are concentrated in the fovea, which is the central region of the retina. The fovea has no rods and is responsible for sharp central vision and color perception. Cones require bright light to function and are responsible for high-acuity vision, particularly in the fovea.
They also code color, and this is based on three types of cones sensitive to different wavelengths, corresponding to the perception of red, green, and blue colors. These cones allow us to distinguish thousands of hues through various combinations of stimuli.
In contrast, rods are distributed throughout the rest of the retina and are specialized for night vision, peripheral vision, and motion detection, as they work well in low-light conditions. Rods lack the color function and spatial resolution that cones have. Considering the high concentration of cones in the fovea, there is low convergence in this region, and each photoreceptor is connected to its own retinal ganglion cell, which results in high visual acuity.
Cones are concentrated in the fovea and responsible for high-acuity color vision, whereas rods are good for night and peripheral vision. Cones require bright light and code for color, while rods are optimized for low-light conditions.