As shown in the configuration, the administrator has configured OSPF on R1, but R1 cannot learn the routes of other routers.

As shown in the configuration, the administrator has configured OSPF on R1, but R1 cannot learn the routes of other routers.

[R1] ospf

[R1-ospf-1] area 1

[R1-ospf-1-area-0.0.0.1] network 10.0.12.0 0.0.0.255

The possible reason is (). (Multiple Choice)
A . This router is not configured with authentication, but the neighbor router is configured with authentication.
B . The OSPF process ID is not configured when this router is configured.
C . The area ID configured by this router is different from the area ID of its neighbor router.
D . This router does not announce the network connecting neighbors when configuring OSP

Answer: ACD