在MSR路由器上，如果想指定ping操作时发送的报文的源地址，应使用（）参数。
A.–s
B.–I
C.–a
D.-d
参考答案：C
---- Have you done well in your English exam ?
----It’s very nice ___ you ___ me with my English, but it’s a pity! I made you ____ .
A．for , to help , disappointing
B．of , to help , disappointed
C．for , helping , to be disappointed
D．of , helping , disappoint
鼻咽纤维血管瘤起源于：（）
A．枕骨底部骨膜
B．蝶骨体骨膜
C．翼突内侧骨膜
D．鼻咽部黏膜
E．鼻中隔后缘黏膜
