单项选择题

A) Router(config) # access-list standard block
Router(config-std-nac1) # deny 10.0.0.0 255.0.0.0 log
Router(config-std-nac1) # deny 172.16.0.0 255.240.0.0
Router(config-std-nac1) # permit any
B) Router(config) # ip access-list standard block
Router(config-std-nac1) # permit any
Router(config-std-nac1) # deny 10.0.0.0 0.255.255.255 log
Router(config-std-nac1) # deny 172.16.0.0 0.15.255.255
C) Router(eonfig) # ip access-list standard block
Router(config-std-nac1) # deny 10.0.0.0 255.0.0.0 log
Router(config-std-nac1) # deny 172.16.0.0 255.240.0.0
Router(config-std-nac1) # permit any
D) Router(config) # ip access-list standard block
Router(config-std-nac1) # deny 10.0.0.0 0.255.255.255 log
Router(config-std-nac1) # deny 172.16.0.0 0.15.255.255
Router(config-std-nac1) # permit any