Question

Choose the odd one out

Myopia, hypermetropia, xerophthalmia, astigmatism

Answer 1

Refractive errors:

1. Myopia is referred to as short sightedness where a person is able to see the near by objects clearly and not the distant objects.
2. Hypermetropia is long sightedness where one can see only distant objects properly but nearby objects are blurred.
3. Astigmatism is visual defect caused due to uneven curvature in lens or cornea.
4. These three are grouped as refractive errors of the eye as it is caused due to the abnormality of the lens or the cornea.

Xerophthalmia:

1. It is the dryness of the cornea caused due to deficiency of vitamin A.

Final answer: The odd one out is xerophthalmia which is a deficiency disorder or the eye while the others are refractive errors.