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What is To facilitate the screening of visual-acuity, WHO defines blindness as counting fingers at a distance of: September 2006 and September 2010 and explain in detail?
Ans. B: 3 meters The WHO proposed a uniform criterion and defined blindness as "visual acuity of less than 3/ 60 (Smellen) or its equivalent" . In order to facilitate the screening of Visual acuity by non-specialized personnel, in the absence of appropriate vision chas, the WHO has now added the "inability to count fingers in daylight at a distance of 3 meters" to indicate less than 3/60 or its equivalent.