Which refractive error is corrected with concave lenses?

• A. Hyperopia
• B. Emmetropia
• C. Myopia
• D. Presbyopia

Answer: (C)

Concave lenses are used to correct myopia. When someone is nearsighted, their eye focuses light in front of the retina, so distant objects appear blurry. A concave lens diverges light slightly before it enters the eye, moving the focus back so it lands on the retina and distant objects come into clear view.

Hyperopia, or farsightedness, is treated with convex lenses that converge light to move the focal point forward onto the retina. Emmetropia means normal vision with no refractive error requiring correction. Presbyopia is age-related difficulty focusing on near objects and is typically corrected with reading glasses, often convex as well.