Each part of the eyeball refracts light to focus the image on which part?

The retina is the correct answer because it is the light-sensitive layer located at the back of the eye that receives light focused by the cornea and lens. Once light is refracted by these structures, the image is projected onto the retina, which converts it into electrical signals that are sent to the brain via the optic nerve. This allows for the perception of images.

In contrast, the pupil is simply an opening that regulates the amount of light entering the eye, but it doesn’t play a role in focusing light. The aqueous humor is the clear fluid that fills the space between the cornea and the lens, providing nutrients and maintaining intraocular pressure, but it also does not have a direct role in focusing light. Lastly, the optic disc serves as the entry point for the optic nerve and contains no photoreceptor cells, meaning it is not involved in the process of image formation; instead, it is the location where vision information exits the eye to be processed by the brain. Thus, the retina is the only option involved in the actual process of focusing light and facilitating vision.