Which of these practices could be harmful to the eyes?

Options

A. Eating a healthy and balanced diet
B. Rubbing the eyes at regular intervals
C. Wearing sunglasses while going out in the sun
D. Using an anti-glare screen on the computer

Answer

### Step-by-Step Solution:

1. **Identify the Practices**: To determine which practices could be harmful to the eyes, we need to consider common activities that people engage in regarding eye care and exposure.

2. **Rubbing the Eyes**: One of the practices mentioned is rubbing the eyes. This action can cause harm to the eyes, especially if done frequently.

3. **Effects of Rubbing**: Rubbing the eyes can lead to several issues:
- **Damage to the Cornea**: The cornea is a sensitive part of the eye, and excessive rubbing can cause scratches or other injuries.
- **Dark Circles**: Rubbing can also lead to the appearance of dark circles around the eyes due to increased blood flow and irritation.

4. **Other Practices**:
- **Sun Exposure**: Going out in the sun without protection can expose the eyes to harmful UV rays.
- **Use of Sunglasses**: Wearing sunglasses can protect the eyes from UV rays, making it a safe practice.
- **Screen Time**: Prolonged exposure to screens can expose the eyes to blue light, which can be harmful. Using anti-glare screens can help mitigate this risk.

5. **Conclusion**: Among the practices discussed, rubbing the eyes is identified as harmful, while wearing sunglasses and using anti-glare screens are protective measures.

### Final Answer:
The practice that could be harmful to the eyes is rubbing the eyes at regular intervals.

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