—Remember how we met for the first time, Dick?

—Of course I do. You _______ to the teachers' office hurriedly and _________ me.

A．had walked; weren't noticing

B．were walking; didn't notice

C．had been walking; noticed

D．walked; had noticed

关于因特网中主机名和IP地址的描述中，正确的是______。

A．一台主机只能有一个IP地址

B．一个合法的外部IP地址在一个时刻只能分配给一台主机

C．一台主机只能有一个主机名

D．IP地址与主机名是一一对应的