—Can you guess _____ the MP4 player yesterday?

—Sorry, I've no idea about it. [ ]

A. how much did he pay for

B. how can he get

C. how much he paid for

D. how he has got

使用Word2007新文件格式有哪些好处？（）

A.文件大小更小。

B.文档故障排除更简单（恢复内容更轻松）。

C.轻松管理文档中的敏感信息。

D.以上全部。