Correct option is A
The correct answer is (A) The iris
Explanation:
• The pupil is the opening in the center of the iris, and its size is controlled by the iris muscles.
• The iris is a muscular diaphragm that adjusts the size of the pupil to control the amount of light entering the eye. In bright light, the iris contracts, making the pupil smaller to reduce the amount of light, and in dim light, the iris expands, making the pupil larger to allow more light in.
Information Booster:
• The iris contains two sets of muscles: the sphincter pupillae (which constricts the pupil) and the dilator pupillae (which dilates the pupil).
• This adjustment is crucial for protecting the retina from too much light and improving vision under varying light conditions.
Additional Knowledge:
The Cornea
• The cornea is the transparent outer layer of the eye that focuses light but does not control the size of the pupil.
The Retina
• The retina is the light-sensitive layer at the back of the eye that detects light and sends signals to the brain but does not control pupil size.
The Lens
• The lens helps focus light onto the retina but does not control the size of the pupil.
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