Keenness of vision is also known as visual ______.

• A. Clarity
• B. Sharpness
• C. Acuity
• D. Focus

Answer: (C)

The keenness of vision is described by the term visual acuity. In eye science, acuity is the precise measure of how sharply you can see details at a distance. It’s the standard phrase used in eye exams and medical texts, often quantified with charts like the Snellen chart (for example, 20/20). That precision is why acuity fits best here: it specifically labels the ability to discern fine details, not just general clarity or the act of focusing.

Clarity is a broad, everyday word that doesn’t name the specific measurement used in eye care. Sharpness is close in meaning but isn’t the established technical term. Focus refers to the lens adjustment or the act of focusing, rather than the overall capacity to distinguish fine details.