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What is WHO definition of blindness, Visual acuity - and explain in detail?
Ans. is 'b' i.e., < 3/60 o WHO defines blindness as "Visual acuity of < 3/60 in better eye with best possible correction".Categories of visual impairmentCategories of visual impairmentVisual acuityMaximum less thanMinimum equal to or better thanLow vision1. 6/182. 6/606/603/60Blindness3. 3/60 (finger counting at 3 metres)4. 1/60 (finger counting at 1 metre)5. No light perception1/60 (finger counting at 1 metres) light perception