Which of the following statements for persons suffering from presbyopia is/are correct? 1. They cannot distinguish colours. 2. It usually develops with ageing. 3. They wear either bi-focal lenses consisting of both concave and convex lenses or progressive lenses. Select the answer using the code given below :
- (a)1 only
- (b)2 only
- (c)1 and 3
- (d)2 and 3
Correct — D, 2 and 3. Presbyopia is the age-related loss of accommodation, and it is corrected with bifocal or progressive lenses; it has nothing to do with colour vision.
- (a)1 only — Statement 1 alone. Inability to distinguish colours is colour blindness, a retinal cone defect, entirely unrelated to presbyopia.
- (b)2 only — Statement 2 is true but incomplete — statement 3 is also correct, so this cannot be the answer.
- (c)1 and 3 — Pairs the false statement 1 with the true statement 3.
Accommodation is the eye's ability to change the focal length of its lens by contracting the ciliary muscle. With age the lens stiffens, the near point recedes, and close work becomes difficult — that is presbyopia.
Because a presbyopic eye often also has a distance error, a single lens will not serve both ranges, which is why bifocals (a convex segment for near, the wearer's distance correction above) or progressive lenses are prescribed. Onset is typically around the age of 40 and it affects essentially everyone eventually.
- Presbyopia = loss of accommodation with age; the near point moves away.
- Myopia is corrected by a concave lens, hypermetropia by a convex lens.
- Colour blindness is a cone-cell defect, most commonly red-green and X-linked.
- Progressive lenses vary power continuously instead of in two discrete zones.
The trap is folding colour blindness into a lens-power question.
- Treating colour blindness as a refractive error.
- Assuming presbyopia is simply hypermetropia.
Eye-defect items are usually statement-based and hinge on one planted statement drawn from a different condition.
No directly related past PYQ was found.
- practice — not a real PYQ
A person can see distant objects clearly but needs glasses to read. The person most likely has
- (a)myopia
- (b)presbyopia or hypermetropia
- (c)astigmatism
- (d)colour blindness
Answer(b) presbyopia or hypermetropia — both push the near point away while distance vision stays good.