Most of the refraction of light takes place in the

Options

A. iris
B. cornea
C. pupil
D. retina

Answer

**Step-by-Step Solution:**

1. **Understanding Refraction**: Refraction is the bending of light as it passes from one medium to another. This bending occurs due to a change in the speed of light in different media.

2. **Identifying the Components of the Eye**: The human eye consists of several parts, including the iris, cornea, pupil, and retina. Each part has a specific function related to vision.

3. **Function of the Iris**: The iris controls the amount of light entering the eye by adjusting the size of the pupil. It does not primarily contribute to the refraction of light.

4. **Function of the Cornea**: The cornea is the transparent front part of the eye that covers the iris and pupil. It is responsible for most of the light refraction in the eye because it has a curved surface that bends light rays entering the eye.

5. **Function of the Pupil**: The pupil is the opening in the center of the iris that allows light to enter the eye. It does not refract light; it simply regulates the amount of light that passes through.

6. **Function of the Retina**: The retina is the light-sensitive layer at the back of the eye where images are formed. It does not refract light; instead, it receives and processes the light that has been refracted by the cornea and lens.

7. **Conclusion**: Based on the functions of these parts, the majority of refraction of light in the human eye occurs at the cornea.

**Final Answer**: Most of the refraction of light takes place in the cornea of the human eye.

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