3.
A, C. The process ID for OSPF on a router is only locally significant and you can use the same number on each router, or each router can have a different number—it just doesn’t matter. The numbers you can use are from 1 to 65,535. Don’t get this confused with area numbers, which can be from 0 to 4.2 billion.
4.
B. The router ID (RID) is an IP address used to identify the router. It need not and should not match.
8.
D. By default the administrative distance of OSPF is 110.
9.
A. Hello packets are addressed to multicast address 224.0.0.5.
11.
A. 224.0.0.6 is used on broadcast networks to reach the DR and BDR.