Presbyopia is caused by:
ADiabetes
BWeakening of ciliary muscles with age
CExposure to bright sunlight
DVitamin A deficiency
Answer & Solution
Correct answer: B. Weakening of ciliary muscles with age
1. Presbyopia is the age-related loss of accommodation.
2. As people age the ciliary muscles weaken and the lens becomes less flexible.
3. The eye loses its ability to focus on near objects.
4. So elderly people often need bifocal reading glasses.
5. The cause is weakening of ciliary muscles and stiffening of the lens.
_Source: NCERT Class 10 Science Ch 11 'Human Eye and the Colourful World'_
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