Which statement best describes near-vision focusing?

Which statement best describes near-vision focusing?

• A. The lens increases curvature to shorten focal length
• B. The cornea flattens
• C. The pupil dilates
• D. The retina sends fewer signals

Answer: (A)

Accommodation drives near-vision focusing: the eye increases its optical power by making the lens more curved. When the ciliary muscle contracts, it releases tension on the zonular fibers, letting the lens thicken and become more convex. This increases the lens’s refractive power, shortening the focal length so light from a nearby object is focused on the retina. The described statement captures this mechanical change—the lens increases curvature to shorten focal length. The cornea’s shape isn’t actively altered for near focus, pupil size varies for lighting and depth of field but isn’t the primary mechanism, and retinal signaling doesn’t change the lens’s curvature.

Accommodation drives near-vision focusing: the eye increases its optical power by making the lens more curved. When the ciliary muscle contracts, it releases tension on the zonular fibers, letting the lens thicken and become more convex. This increases the lens’s refractive power, shortening the focal length so light from a nearby object is focused on the retina. The described statement captures this mechanical change—the lens increases curvature to shorten focal length. The cornea’s shape isn’t actively altered for near focus, pupil size varies for lighting and depth of field but isn’t the primary mechanism, and retinal signaling doesn’t change the lens’s curvature.