多项选择题 Refer to the exhibit. A network administrator wants to reduce the number of OSPF routes advertised from Area 1 into Area 2. As the router configuration specialist, what two things would you do to accomplish this goal?（）

多项选择题 Refer to the exhibit. A company would prefer all Internet - bound OSPF routed traffic to use ISP ABC with ISP DEF as a backup. As the network consultant, what three configuration changes might you make?（）

单项选择题 Which functionality is required within an IP router that is situated at the boundary of an IPv4 network and an IPv6 network to allow communication between IPv6- only and IPv4 - only nodes?（）