What causes nearsightedness, farsightedness, and astigmatism?
A)The blind spot is abnormally large or small.
B)Incoming light signals are not properly focused on the retina.
C)The iris and cornea do not function properly.
D)Accommodation does not take place.

Question

Quizplus · Accepted Answer

Nearsightedness (myopia) is caused by the eyeball being too long or the cornea being too curved, causing incoming light to focus in front of the retina. Farsightedness (hyperopia) is caused by the eyeball being too short or the cornea being too flat, causing incoming light to focus behind the retina. Astigmatism is caused by an irregularly shaped cornea, causing light to be focused unevenly on the retina. All of these conditions result in incoming light signals not properly focusing on the retina.

What Causes Nearsightedness, Farsightedness, and Astigmatism