 The figure shows an eye defect in which parallel light rays from a distant object converge at a point in front of the retina. This defect, and the lens used to correct it, are:
AHypermetropia (long-sightedness), corrected by a convex lens
BMyopia (short-sightedness), corrected by a concave lens
CAstigmatism, corrected by a cylindrical lens
DPresbyopia, corrected by a bifocal lens
Answer & Solution
Correct answer: B. Myopia (short-sightedness), corrected by a concave lens
**Identify the defect.** Distant rays converging *in front of* the retina means the eye is over-converging — the eyeball is too long (or the lens too powerful). This is **myopia** (short-sightedness): the person sees nearby objects clearly but distant objects appear blurred.
**Correction.** A **concave (diverging) lens** in front of the eye spreads the incoming rays out before they hit the eye lens, so the effective focal point shifts back onto the retina.
**Why the distractors are tempting.**
- Hypermetropia is the *opposite* — image forms *behind* the retina, corrected by a convex lens (option A).
- Astigmatism is irregular curvature, corrected by a *cylindrical* lens (option C).
- Presbyopia is age-related loss of accommodation, corrected by bifocals (option D).
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