Ⅰ.阅读理解(共15小题；每小题2分，满分30分)
阅读下列短文，从每题所给的四个选项(A、B、C和D)中，选出最佳选项。
A
Mark Twain left school when he was twelve.He had little school education.In spite of this，he became the most famous writer of his time.He made millions of dollars by writing.His real name was Samuel Langhorne Clemens，but he is better known all over the world as Mark Twain，his penname.
