Mary ______ to see you . She _____ for you downstairs at the moment .

A．has come ; is waiting

B．came ; is waiting

C．has come ; waited

D．came ; was waiting

在Excel中，修改工作表名字的操作可以从（）工作表标签开始。

A.用鼠标左键双击

B.用鼠标右键双击

C.按住Alt键同时用鼠标左键双击

D.用鼠标左键单击