Final Answer:
The highlighted eye structure is the iris.
Step-by-step explanation:
The iris is the visible colored part of the eye that surrounds the pupil. It's composed of muscular tissue with pigmentation, giving the eye its distinctive color. The primary function of the iris is to regulate the amount of light entering the eye by controlling the size of the pupil.
Through its intricate muscles, the iris adjusts the pupil's size in response to varying light conditions, expanding in dim light and contracting in bright light. This mechanism helps to protect the sensitive structures within the eye and ensures optimal vision.
The iris holds a significant role in determining the eye's appearance, as its color and pattern are unique to individuals and can vary widely, ranging from shades of brown, blue, green, or gray. Additionally, the iris plays a crucial role in biometric identification due to its distinctiveness.
Here is complete question;
"Which of the following is the highlighted eye structure: cornea, lens, retina, iris?"