**Core Concept**
Blindness is a significant visual impairment that affects a person's ability to perform daily activities. According to the World Health Organization (WHO), blindness is defined based on the level of visual acuity and the extent of visual field loss.

**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, or a visual field of less than 10 degrees in the better eye. This definition aims to provide a standardized measure of blindness, allowing for effective planning and implementation of eye care services. The visual acuity of 3/60 represents a severe impairment, where a person can only recognize shapes and objects with great difficulty.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not specify the correct criteria for blindness, such as visual acuity or visual field loss.
**Option B:** This option is incorrect because it mentions a different threshold for visual acuity, which does not align with the WHO's definition of blindness.
**Option C:** This option is incorrect because it refers to a different condition, such as low vision, which is a broader term that encompasses various degrees of visual impairment.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that the WHO's definition of blindness serves as a benchmark for eye care services and advocacy efforts worldwide. Understanding this definition is crucial for healthcare professionals working in ophthalmology and public health.

**Correct Answer: C. Low vision is a visual impairment that is not correct for blindness.