The muscle that controls the size of the pupil and thus the amount of light entering the eye is the:
A) iris.
B) cornea.
C) retina.
D) fovea.

Question

Quizplus · Accepted Answer

The iris is responsible for controlling the size and diameter of the pupil, which in turn regulates the amount of light that enters the eye. The other options (cornea, retina, fovea) are important structures in the eye but are not responsible for controlling the size of the pupil.

The Muscle That Controls the Size of the Pupil and Thus