A.IPv4不好使用 B.政府推動 C.IPv6比IPv4更先進 D.IPv4地址短缺
A.192.168.1.0-192.168.15.0匯聚成192.168.0.0/255.255.224.0 B.192.168.1.0-192.168.15.0匯聚成192.168.0.0/255.255.240.0 C.192.168.1.0-192.168.15.0匯聚成192.168.0.0/255.255.248.0 D.192.168.1.0-192.168.15.0匯聚成192.168.0.0/255.255.252.0
A.172.128.0.0/21 B.172.128.17.0/21 C.172.128.12.0/22 D.172.128.20.0/20