Which part of the eye controls the amount of light entering the pupil?

Options

A. Sclera
B. Iris
C. Eye lens
D. Cornea

Answer

**Step-by-Step Solution:**

1. **Identify the Question:** The question asks which part of the eye controls the amount of light entering the pupil.

2. **Understand the Structure of the Eye:** The eye consists of several parts, including the cornea, lens, pupil, and iris. Each part has its specific function.

3. **Define the Iris:** The iris is the colored part of the eye that surrounds the pupil. It is responsible for controlling the size of the pupil.

4. **Function of the Iris:** The iris regulates the amount of light that enters the eye by adjusting the size of the pupil. When there is bright light, the iris constricts the pupil to allow less light in. Conversely, in dim light, the iris dilates the pupil to let in more light.

5. **Conclusion:** Therefore, the part of the eye that controls the amount of light entering the pupil is the iris.

**Final Answer:** The iris controls the amount of light entering the pupil.

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