................ act as shutters of eye.

Explanation

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks which structure acts as the shutters of the eye.

2. **Understand the Function of Eyelids**: The eyelids are folds of skin that cover the eye. They play a crucial role in protecting the eye and regulating the amount of light that enters.

3. **Describe the Eyelids**: The eyelids consist of two parts: the upper eyelid and the lower eyelid. When the eyelids close, they cover the eye, similar to how shutters work on a window.

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