The correct answer is: C. adds to the curvature correction.
Refraction correction is the process of correcting the way light is bent as it passes through the eye. This is done by using lenses to change the direction of the light rays so that they focus properly on the retina.
Curvature correction is the process of correcting the shape of the cornea. The cornea is the clear front part of the eye that helps to focus light. If the cornea is too curved or too flat, it can cause vision problems.
Refraction correction and curvature correction are two different processes that are often used together to correct vision problems. Refraction correction is used to correct the way light is bent, while curvature correction is used to correct the shape of the cornea.
Option A is incorrect because refraction correction does not completely eliminate curvature correction. Option B is incorrect because refraction correction does not partially eliminate curvature correction. Option D is incorrect because refraction correction does have an effect on curvature correction.