题目

American popular music is played all over the world. People of all ages in all countries enjoy  61  (listen) to it. The reasons for  62  popularity are its fast pace and rhythmic beat. The music has many origins in the United States. Country music,  63  (come) from the rural areas in the southern United States, is one source. Many people appreciate this music because of the emotions  64  (express) by country music songs. A second origin of American popular music si the blues. It described mostly sad feelings  65  (reflect) the difficult lives of American blacks. It is usually 由8个亿，80个万和800个一组成的数是( )。A. 880800 B. 80800800 C. 800800800