Which layer delivers blood to the retina and contains pigment to prevent internal reflection?

• A. Sclera
• B. Iris
• C. Choroid
• D. Retina

Answer: (C)

The layer that both nourishes the retina and helps prevent internal reflection is the choroid. It sits between the sclera and the retina and is rich in blood vessels, supplying nutrients and oxygen to the outer retina and photoreceptors via the choroidal circulation. Its dark pigment, mainly melanin, absorbs stray light that passes through the retina, reducing scattering and glare that would blur vision. The sclera is the tough outer coat that protects and shapes the eye but doesn’t deliver blood to the retina or contain pigment to suppress reflection. The iris regulates the amount of light entering the eye and has pigment for color, but its job isn’t to nourish the retina. The retina itself is the light-detecting tissue and relies on the choroid for nourishment rather than providing it.