Light rays A and B fall on an optical component X and come out as C and D. The optical component is

A. Concave
B. Convex
C. Prism
D. None of these.

Hint:The lens which generally diverges incident rays on them is known as a concave lens. The lens which converges incident rays of light is known as a convex lens. An arrangement that splits a single ray of light incident on them into several wavelengths is called prism. As you can see from the diagram given above, A and B are two incident rays falling on an unknown component X. Also you can see from the above diagram rays C and D getting diverged from the initial direction of incident rays. Using this information, we can find out the correct answer.

Complete step by step answer:
As the rays in the given diagram diverge and we know that the component which diverges incident rays falling on them from their initial direction is known as a concave lens, thus the given component in the above diagram is a concave lens.

Hence option A is the correct answer.

Note:A lens is a combination of two curved mirrors that diverts the incident light from its path, An incident ray undergoes refraction twice, once while entering the lens and then while leaving the lens. There are mainly two types of lenses – concave lens and convex lens. Both of them have different properties so they refract the light in different ways. The image of the object placed depends on the position of the object.