Presbyopia arises because:
AThe ciliary muscles weaken and the lens loses flexibility with age
BThe retina detaches
CThe optic nerve thickens (option)
DThe iris loses pigment
Answer & Solution
Correct answer: A. The ciliary muscles weaken and the lens loses flexibility with age
1. Presbyopia is an age-related loss of accommodation.
2. It is caused by weakening of ciliary muscles and reduced lens flexibility.
3. Near vision becomes hard; reading glasses (convex lenses) are needed.
_Source: NCERT Class 10 Science, Ch 10 "The Human Eye and the Colourful World", §10.2_
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