Which defect of vision can be rectified using a concave lens ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Vision Defects**: The first step is to recognize that there are various defects of vision, such as myopia (near-sightedness), hyperopia (far-sightedness), and astigmatism. Each of these defects has specific characteristics and requires different corrective measures.

2. **Identifying Myopia**: Myopia, also known as near-sightedness, is a condition where a person can see nearby objects clearly, but distant objects appear blurry. This occurs because the light rays from distant objects converge before they reach the retina.

3. **Role of Concave Lens**: To correct myopia, a concave lens is used. A concave lens diverges light rays that are coming from a distance. This means that the lens spreads out the light rays before they enter the eye.

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