What does the passage mainly discuss?

Câu hỏi :

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions

We get great pleasure from reading. The more advanced a man is, the greater delight he will find in reading. The ordinary man may think that subjects like philosophy or science are very difficult and that if philosophers and scientists read these subjects, it is not for pleasure. But this is not true. The mathematician finds the same pleasure in his mathematics as the school boy in an adventure story. For both, it is a play of the imagination, a mental recreation and exercise. The pleasure derived from this activity is common to all kinds of reading. But different types of books give us different types of pleasure. First in order of popularity is novel-reading. Novels contain pictures of imaginary people in imaginary situations, and give us an opportunity of escaping into a new world very much like our world and yet different from it. Here we seem to live a new life, and the experience of this new life gives us a thrill of pleasure. Next in order of popularity are travel books, biographies and memoirs. These tell us tales of places we have not seen and of great men in whom we are interested. Some of these books are as wonderful as novels, and they have an added value that they are true. Such books give us knowledge, and we also find immense pleasure in knowing details of lands we have not seen and of great men we have only heard of. Reading is one of the greatest enjoyments of life. To book-lovers, nothing is more fascinating than a favorite book. And, the ordinary educated man who is interested and absorbed in his daily occupation wants to occasionally escape from his drudgery into the wonderland of books for recreation and refreshment. 

What does the passage mainly discuss?