—What’s wrong with your ipad? The soundis not clear.—Yes. It has been broken for some time

问题补充：

—What’s wrong with your ipad? The soundis not clear.

—Yes. It has been broken for some time.

A. come out

B. coming out

C. to come out

D. came out

答案：

A. come out

(答案→)B. coming out

C. to come out

D. came out

解析：本题考查非谓语动词。所修饰名词The sound与come out之间的关系为主动关系，故用现在分词，选B。