If a 55-year-old patient experiences progressively worsening blurred vision at close range despite wearing glasses, what distinguishes the mechanism causing this from simple refractive error?

💡 Explanation

Presbyopia results from decreasing elasticity of the lens and reduced ciliary muscle function with age. This reduced compliance impairs accommodation, because the ciliary muscle can no longer effectively change the lens shape for near focus; therefore, option C is correct, rather than corneal shape or retinal factors causing the blur.

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