_________ is known to us all is that the 2008 Olympic Games will take place in Beijing.

A．It

B．What

C．As

D．Which

电子化支局系统中4查询-24给据邮件跟踪查询功能里可以查询（）。

A.邮件当前状态查询

B.邮件全程跟踪查询

C.邮件收寄信息查询

D.邮件投递信息查询