Accommodation of eye is due to

Options

A. Ciliary muscles
B. iris muscles
C. Aqueous fluid
D. Vitreous fluid

Answer

**Step-by-Step Solution:**

1. **Understanding Accommodation**:
- Accommodation refers to the process by which the eye adjusts its optical power to maintain a clear image of an object as its distance from the eye changes. This is essential for focusing on both near and distant objects.

2. **Role of the Lens**:
- The eye contains a flexible lens that changes shape to focus light onto the retina. When an object is close, the lens becomes more rounded (convex), and when the object is far away, the lens flattens.

3. **Muscles Involved**:
- The change in the shape of the lens is controlled by specific muscles. The primary muscles responsible for this adjustment are the ciliary muscles.

4. **Function of Ciliary Muscles**:
- The ciliary muscles contract or relax, which alters the tension on the lens. When the ciliary muscles contract, the lens becomes thicker, allowing for better focus on nearby objects. Conversely, when they relax, the lens flattens for distant objects.

5. **Evaluating the Options**:
- **Ciliary Muscles**: Correct answer, as they control the shape of the lens for accommodation.
- **Iris Muscles**: Incorrect, as they are responsible for controlling the size of the pupil, not the lens shape.
- **Aqueous Fluid**: Incorrect, as it provides nutrients to the eye but does not play a role in accommodation.
- **Vitreous Fluid**: Incorrect, as it helps maintain the shape of the eye but does not influence lens shape.

6. **Conclusion**:
- The correct answer to the question "Accommodation of eye is due to" is the **ciliary muscles**.

**Final Answer**: Ciliary muscles.

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