What visual defect occurs when the eyeball is elongated from front to back, causing light rays from distant objects to focus in front of the retina?
Answer and explanation
Correct answer: A. myopia, corrected by a concave lens
- Step 1: In myopia (short-sightedness), the eyeball is too long or the refractive power of the lens/cornea is too strong. Step 2. Parallel light rays from distant objects converge in front of the retina, causing distant blur. Step 3. A diverging (concave) lens spreads the light rays, pushing the focal point onto the retina. Answer: myopia (short-sightedness), corrected by a concave lens. Why not the others: Hypermetropia is short eyeball corrected by convex lens; astigmatism involves uneven corneal curvature; presbyopia is age-related lens stiffening.
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