Which of the following is a characteristic of the lens?
a. the lens focuses light on the retina.
b. the lens of the human eye has a concave shape.
c. the lens is vascularized.
d. in a healthy eye, the lens will be opaque.

A. the lens focuses light on the retina

The lens is composed of transparent, flexible tissue and is located directly  behind the iris and the pupil. it is the secondary part of the eye after the cornea. by changing it's shape the lens changes the focal distance of the eye and focuses the light that passes through it and into the retina in order to create clear images of objects. it also works together with the cornea to refract, or bend light.

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