Blindness as defined by WHO is the visual acuity of less than
**Blindness Definition by WHO**
**Core Concept**
The World Health Organization (WHO) defines blindness based on visual acuity, which is a measure of the sharpness of vision. According to the WHO, blindness is a significant visual impairment that affects a person's quality of life.
**Why the Correct Answer is Right**
The WHO defines blindness as a visual acuity of less than 3/60 in the better eye with the best possible correction. This means that an individual with a visual acuity of 3/60 or worse in their better eye is considered blind. This definition is used globally to measure the prevalence of blindness and to track progress towards reducing blindness rates.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not a valid definition of blindness according to the WHO. The correct definition requires a visual acuity of less than 3/60, not just any value below 1.
* **Option B:** This option is incorrect because it does not specify the better eye, which is an essential part of the WHO's definition. Blindness is defined based on the better eye, not the worse eye.
* **Option C:** This option is incorrect because it does not provide a specific visual acuity value. Blindness is defined as a specific level of visual impairment, which cannot be determined without a specific value.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the WHO's definition of blindness is based on visual acuity in the better eye, not the worse eye. This distinction is crucial for accurate diagnosis and tracking of blindness rates.
**Correct Answer:** 3/60.