Which part of the eye is a muscle that regulates the size of the pupil?
A) iris
B) lens
C) retina
D) sclera

Question

Quizplus · Accepted Answer

The iris is the part of the eye that contains muscle fibers that regulate the size of the pupil. The pupil itself is the opening in the center of the iris through which light enters the eye. When the iris constricts, the pupil gets smaller, and when the iris dilates, the pupil gets larger.

Which Part of the Eye Is a Muscle That Regulates