Convex lenses are used for

Options

A. Myopia
B. Hypermetropia
C. A little vision
D. None of the above

Explanation

**Step-by-Step Solution:**

1. **Understanding Convex Lenses**: Convex lenses are thicker in the middle and thinner at the edges. They converge light rays that pass through them.

2. **Application in Vision Correction**: Convex lenses are primarily used to correct hypermetropia (farsightedness). In hypermetropia, the eye cannot focus on nearby objects because the image is formed behind the retina.

3. **Image Formation in Hypermetropia**: In a normal eye, light rays from an object converge on the retina. However, in a hypermetropic eye, the light rays converge behind the retina, leading to blurred vision for nearby objects.

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