In the question four words are given. Which of them will come in the last if all of them are arrange alphabetically as in a dictionary?

LESSON

If the words are arranged alphabetically, the order would be as follows:  LANGUAGE, LEPROSY, LESSEN, LESSON

So, the answer is: LESSON

In order to understand how we came to this answer, we need to first understand the following example and then solve the above question accordingly.