Question

Too short an eyeball or too flat a lens produces
(A)Nearsightedness
(B)Astigmatism
(C)Myopia
(D)Hypermetropia

Answer 1

Hint: Refractive error of eyes occurs due to several reasons such as abnormal length of the eyeball or sometimes environmental factors and aging. This kind of situation results in the inability of the eye to focus the image on the retina and therefore causes blurred vision at certain distances.

Complete answer:
Farsightedness or Hypermetropia is caused when the eyeball of a person is too short or the lens of the eyes is too flat. In such cases, the eyes are not able to focus the incoming light on the retina wall, instead focus it behind it due to insufficient accommodation by the lens. The person suffering from Hypermetropia can see the distant objects clearly but can not see the near objects without blurry vision.

Additional Information: Nearsightedness or myopia is caused due to the length of the eyeball growing too long or the lens being too strong. Then the eye fails to focus the incoming light on the retina but focuses it in front of it. This causes the close objects to appear normal but the distant objects appear blurry. The risk factors include working indoors, family history of the disease, etc.
Astigmatism is another error of the eye in which the light isn't focused on the retina evenly and results in a distorted vision at any distance. The symptoms of this disorder include eyestrain, troubled driving at night, and headaches.
So, the correct answer is “Hypermetropia”.

Note: A common disease related to the eyes is a refractive error that occurs when the eye can not focus the incoming light properly and causes blurred vision. The most common refractive errors are- Myopia or Nearsightedness, Hypermetropia or farsightedness, Astigmatism, and Presbyopia. We already discussed the first three in the answer. Presbyopia is mainly related to aging and occurs universally. It is the difficulty in reading or seeing clearly at arm's length.