Iris of an is an extension of

Options

A. Sclerotic
B. Choroid/Uvea
C. Choroid and retina
D. Selerotic and choroid.

Answer

**Step-by-Step Solution:**

1. **Understanding the Structure of the Eye**: The human eye is composed of three distinct layers: the outer layer, the middle layer, and the inner layer.

2. **Identifying the Middle Layer**: The middle layer of the eye contains several important structures. Among these are the choroid, ciliary body, and iris.

3. **Describing the Choroid**: The choroid is a dark pigmented, thin vascular layer located in the middle portion of the eye. It plays a crucial role in providing nutrients to the eye and absorbing excess light.

4. **Recognizing the Ciliary Body**: The ciliary body is formed from the thickening of the choroid in the anterior (front) part of the eye. It is involved in the accommodation of the lens for focusing.

5. **Defining the Iris**: The iris is a donut-shaped structure that is an extension of the choroid. It is located at the front of the eye and is the colored part of the eye.

6. **Function of the Iris**: The primary function of the iris is to regulate the size of the pupil, which controls the amount of light entering the eye.

7. **Conclusion**: Based on the above information, we can conclude that the iris is an extension of the choroid.

**Final Answer**: The iris is an extension of the choroid.

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