With ageing, the power of accommodation of the human eye decreases, causing difficulty in viewing nearby objects clearly. This defect is known as:
Presbyopia
Presbyopia is the age-related loss of the eye's power of accommodation. It occurs because the crystalline lens hardens and the ciliary muscles weaken, so the lens can no longer become sufficiently convex to focus rays from nearby objects onto the retina.
Myopia (short sight) and hypermetropia (long sight) are usually present from a young age and arise from the eyeball's shape or lens power; astigmatism is due to an unevenly curved cornea. The age-linked near-vision defect specifically is presbyopia.
Hence, the answer is Presbyopia.
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A. Rear View mirrors in vehicles
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D. Kaleidoscope
What is the reason for formation of Mirage in desert?
