Four pairs of words are given out of which the words in three pairs are related in some way and words in one pair are different. Find out that pair which is differently related.

The answer is D. Oil and Lamp.

In the other three pairs, the first word is a container for the second word. A pen contains a nib, a water bucket contains water, and an inkpot contains ink. However, an oil lamp does not contain oil. The oil is burned in the lamp, not contained by it.

Here are some additional details about each pair:

• A pen contains a nib. The nib is the part of the pen that writes. It is made of metal or plastic and has a sharp point that can be used to make marks on paper.
• A water bucket contains water. The bucket is a container that is used to hold water. It is usually made of plastic or metal and has a handle that makes it easy to carry.
• An inkpot contains ink. The inkpot is a container that is used to hold ink. It is usually made of ceramic or glass and has a lid that keeps the ink from drying out.
• An oil lamp does not contain oil. The oil is burned in the lamp, not contained by it. The lamp has a wick that is soaked in oil. When the wick is lit, the oil burns and provides light.