A.route add–net192.168.1.0 gw 192.168.1.1 netmask 255.255.255.0 metric1
B.route add–net172.16.1.0 gw 192.168.1.1 netmask 255.255.255.255 metric1
C.route add–net172.16.1.0 gw 172.16.1.1 netmask 255.255.255.0 metric1
D.route add default 192.168.1.0 netmask 172.168.1.1 metric1