If a 55-year-old individual is prescribed reading glasses due to presbyopia, which mechanism explains why focusing on near objects becomes difficult, despite sufficient light?

💡 Explanation

Presbyopia occurs because the lens loses elasticity with age, which reduces its ability to change shape. The ciliary muscles can still contract, but they cannot effectively increase the lens's curvature for near focus; therefore, near objects appear blurry, rather than a problem with pupillary constriction or retinal sensitivity.

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