Respuesta :
The answer is C. Iris. It's made up of muscle fibers which help control the size of the pupil. I hope you find this answer the most helpful! :)
Answer:
C. The iris.
Explanation:
The iris controls the size of the pupil by making it so when light enters the eye through the pupil, the iris will regulate the amount of light by controlling the expanding the pupil or minimizing it.