1. [单选题]Your network uses the172.12.0.0 class B address. You need to support 459 hosts per subnet, while accommodating the maximum number of subnets. Which mask would you use?
A. 255.255.0.0.
B. 255.255.128.0.
C. 255.255.224.0.
D. 255.255.254.0.
E. None of the above
2. [单选题]下列路由协议中，属于链路状态路由协议的是（）
A. RIP
B. EIGRP
C. IGRP
D. OSPF
