The answer is letter C.
Astigmatism
is a vision problem that causes an individual to see blurry images at all
distances. This is due to the irregular shape of the cornea and/or sometimes
the irregular curvature of the lens inside the eyes. When this happens the retina
is prevented from focusing the light that enters causing blurry images at any
distance. This condition is very common and the degree of its severity varies
from person to person. It frequently occurs with other vision problems like
nearsightedness and farsightedness.
