—So hard _____ in the past few months that he has made great progress in English.

—I can see that; only a few mistakes _____ in the exam.

A．has he worked; did he make

B．he has worked; did he make

C．he has worked; he made

D．has he worked; he made

在一台Cisco路由器的g0/1端口上，用标准访问控制列表禁止源地址为10.0.0.0-10.255.255.255和172.16.0.0-172.31.255.255的数据包进出路由器。下列access-list配置，正确的是______。

A．Router (config) #access-list 30 deny 10.0.0.0 0.255.255.255 log
Router (config) #access-list 30 deny 172.16.0.0 0.15.255.255
Router (config) #access-list 30 permit any
Router (config) #interface g0/1
Router (config-if) #ip access-group 30 in
Router (config-if) #ip access-group 30 out
B．Router (coilfig) #access-list 30 deny 10.0.0.0 255.255.255.0 log
Router (config) #access-list 30 deny 172.16.0.0 255.240.0.0
Router (config) #access-list 30 pemlit any
Router (config) #interface g0/1
Router (config-if) #ip access-group 30 in
Router (config-if) #ip access-group 30 out
C．Router (config) #access-list 100 deny 10.0.0.0 0.255.255.255 log
Router (config) #access-list 100 deny 172.16.0.0 0.15.255.255
Router (config) #access-list 100 permit any
Router (config) #interface g0/1
Router (config-if) #ip access-group 100 in
Router (contig-if) #ip access-group 100 out
D．Router (config) #interface g0/1
Router (config-if) #ip access-group 99 in
Router (config-if) #ip access-group 99 out
Router (config-if) #exit
Router (config) #access-list 99 deny 10.0.0.0 0.255.255.255 log
Router (config) #access-list 99 deny 172.16.0.0 0.15.255.255
Router (config) #access-list 99 permit any