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The eye defect presbyopia, in which a person loses the power of accommodation for both near and distant vision, is usually corrected using which kind of lens?
AA single concave lens
BA convex mirror
CBifocal lenses
DA single convex lens
Answer & Solution
Correct answer: C. Bifocal lenses
1. Presbyopia is old-age loss of accommodation affecting both far and near vision.
2. Distant vision needs a concave correction and near vision needs a convex correction.
3. Bifocal lenses combine a concave upper part and a convex lower part to handle both.
4. A single concave or convex lens corrects only one defect, so those options fail.
_Source: Samacheer Kalvi (TN SCERT) Class 10 Science, Unit 2 Optics "Defects in Eye", p.32_
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