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
George Gershwin，born in 1898，was one of America's greatest composers.He published his first song when he was eighteen years old.During the next twenty years he wrote more than five hundred songs.
