What are the four refractive media of the eye?

The correct answer identifies the four primary refractive media of the eye: the cornea, crystalline lens, aqueous humor, and vitreous humor. Each of these components plays a crucial role in focusing light onto the retina, which is essential for clear vision.

The cornea is the transparent front part of the eye that begins the process of light refraction. It provides most of the eye's optical power. The crystalline lens, positioned directly behind the iris, fine-tunes the focus, allowing for accommodation to see objects clearly at various distances. The aqueous humor is the clear fluid in the space between the cornea and the lens that helps maintain intraocular pressure and provides nutrients to the avascular cornea and lens. The vitreous humor is the gel-like substance filling the space between the lens and the retina, helping to maintain the shape of the eye and supporting the retina.

In contrast, the other options include components that are not primarily refractive media. For instance, while the pupil and iris are parts of the eye's anatomy that control the amount of light entering, they do not contribute to the refraction of light. Similarly, the sclera is the eye's white outer layer and does not play a role in bending light. The ciliary