The size of the pupil is adjusted by a doughnut-shaped ring of muscles called the
A) fovea.
B) cornea.
C) iris.
D) lens.

Question

Quizplus · Accepted Answer

The iris is the doughnut-shaped ring of muscles that controls the size of the pupil. The fovea is a small depression in the retina, the cornea is the clear outer layer of the eye, and the lens is the transparent structure behind the iris that helps to focus light onto the retina.

The Size of the Pupil Is Adjusted by a Doughnut-Shaped