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A boy can see distant objects clearly but cannot read his textbook held at 25 cm. He suffers from:
AMyopia
BHypermetropia
CPresbyopia
DCataract
Answer & Solution
Correct answer: B. Hypermetropia
1. He sees distant objects well, so his far point is fine.
2. He cannot see clearly at 25 cm, so his near point lies farther.
3. Pushed-back near point is the defining feature of hypermetropia.
4. Convex lenses of suitable focal length correct it.
5. So the defect is hypermetropia.
_Source: NCERT Class 10 Science Ch 11 'Human Eye and the Colourful World'_
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