Question

Match the items in list-I with items in list-II and collect the correct answers from the codes given below the lists:

List-I	List-II
I. Myopia	A. Bifocal lens
II. Hyper-metropia	B. Cylindrical lens
III. Presbyopia	C. Concave lens
IV. Astigmation	D. Convex lens

A. I−A,II−C,III−B,IV−D
B. I−B,II−D,III−C,IV−A
C. I−D,II−B,III−A,IV−C
D. I−D,II−A,III−C,IV−B

Answer 1

Hint: Human eyes eventually lose their ability to accommodate, as you may have seen. In such circumstances, the person is unable to see well or comfortably. Myopia (nearsightedness), Hypermetropia (farsightedness), and Presbyopia (presbyopia) are the three most prevalent eye abnormalities. The adoption of appropriate spherical lenses corrects these flaws.

Complete answer:
Near-sightedness or short-sightedness are other terms for myopia. The light beams do not focus on the retina's surface, but rather on the area in front of it. As a result, pictures appear fuzzy when seen. In this example, distant pictures are out of focus, while local things are plainly visible. Myopia is sometimes known as near-sightedness or short-sightedness because of this. Shortsightedness is treated by a concave (inwardly curved) lens put in front of a myopic eye, which moves the picture back to the retina and improves clarity.

Hyperopia is a refractive defect that causes distant objects to look clear while close ones appear fuzzy. People react to farsightedness in different ways, and some people, especially when they are young, are unaware that they have a problem with their vision. Furthermore, vision for things at any distance, close or distant, might be hazy for those with substantial farsightedness. The inability of the eye to focus on adjacent things is known as hyperopia. The farsighted eye has no trouble seeing objects that are far away. The lens is no longer capable of assuming the convex and curved form lens required to observe adjacent objects.A converging lens can be used to remedy this visual impairment.

Astigmatism is a vision blurring optical imperfection. Let us first examine how the eye sees light before discovering what creates this problem. When light passes through a perfectly spherical lens (like a basketball), it refracts or bends equally. The light that enters the lens is refracted more in one direction than the other if the lens is not entirely spherical. A person with astigmatism can't focus on both horizontal and vertical lines at the same time. Eyeglasses with cylindrical lenses oriented to compensate for abnormalities in the cornea can be used to remedy this problem.

Presbyopia is a condition that occurs as a result of the normal ageing of the eye. Over time, the ciliary muscles lose their optimal working power and cease to operate properly. Even the crystalline lens loses its flexibility with time (it begins to harden), lowering its focusing capacity. Presbyopia can be cured with simple eyeglasses with convex lenses, just as hyperopia (positive power). In this case, contact lenses can also be used. Despite the fact that they are more convenient, both myopia and presbyopia can occur. It is preferable to use bi-focal lenses in this situation.

Hence option C is correct.

Note: Progressive lenses are similar to bifocal lenses in appearance and function. The main difference is that the gap between the concave and convex lenses is not apparent. The transition is more fluid here. It adds to the level of comfort.