Rogets Thesaurus is a book, and a very famous book, too. If youve never heard of it, dont

worry. But once you know it, it is a friend for life. And dont worry about the title. Roget is the man who wrote it, and "thesaurus" is from a Greek word meaning "treasure". Rogets Thesaurus is not a book which you read from cover to cover. And it certainly isnt a book which fills you with excitement the moment you open it. But it is a book you keep coming back to year after year, again and again, if you are interested in ... words. It is a vast treasure house of information about words. Briefly, it works in the opposite way to a dictionary. When you use a dictionary you know the word, but you dont know what it means. You use a dictionary to find out the meaning of the word. When you use a thesaurus, or the Thesaurus, as there is only one, and that is Rogets Thesaurus, you know about what the word means, but you cant find exactly the word you want. So you look up a related word in the index at the back of the book, then turn to the group or category of words with that meaning, and, well ... if youre lucky, youll soon have found your missing word. Rogets Thesaurus was first published in 1852, and in the next 125 years, that is by 1977, had sold over thirty million copies. Roget himself was a most remarkable man. He was already seventy when he wrote the book, and had spent a most active life as a scientist, physician and engineer. He had made several discoveries, and had published an important report on Londons water supply, which at that time(1827)was very polluted. His thesaurus was a hobby, or a sideline—something to do in his retirement. Indeed, in 1852, it is doubtful if anyone realized just what an important book it was. There were only a thousand copies of the first edition. But it was soon reprinted, and by the time of his death, Roget, who lived to the age of ninety, had seen twenty-five editions of his work printed. And the book is still going strong today, a century and a quarter later. There is most probably a copy in your library. But if you use it, do so with care. Dont try to use all the words which Dr. Peter Mark Roget put into each of his categories. If you do that you may have to go back to the dictionary to find out what some of them mean. Question: This passage is most likely______.

A．a book review

B．an advertisement

C．an editorial

D．a special report