Which three issues cause this behavior? (Choose three.)

You run the operational-mode command show ospf neighbor and notice that an expected OSPF neighbor on a broadcast link is not detected.
Which three issues cause this behavior? (Choose three.)

A.
A problem exists with the physical link or Data Link Layer connectivity.

B.
The router IDs on the two devices do not match.

C.
The IP subnet mask does not match on each end of the link.

D.
The area type does not match on each end of the link.

E.
The AS number on the two devices do not match.

Explanation:
user@host> show ospf neighbor

Address Intf State ID Pri Dead
192.168.254.225 fxp3.0 2Way 10.250.240.32 128 36
192.168.254.230 fxp3.0 Full 10.250.240.8 128 38
192.168.254.229 fxp3.0 Full 10.250.240.35 128 33
10.1.1.129 fxp2.0 Full 10.250.240.12 128 37
10.1.1.131 fxp2.0 Full 10.250.240.11 128 38
10.1.2.1 fxp1.0 Full 10.250.240.9 128 32
10.1.2.81 fxp0.0 Full 10.250.240.10 128 33

Meaning

The output shows a list of the Services Router’s OSPF neighbors and their addresses, interfaces, states, router IDs, priorities, and number of seconds allowed for inactivity (dead time). Verify the following information:

* Each interface that is immediately adjacent to the Services Router is listed.
* The Services Router’s own loopback address and the loopback addresses of any routers with which the Services Router has an immediate adjacency are listed.
* Under State, each neighbor shows a state of Full. Because full OSPF connectivity is established over a series of packet exchanges between clients, the OSPF link might take several seconds to establish. During that time, the state might be displayed as Attempt, Init, or 2way, depending on the stage of negotiation.

If, after 30seconds, the state is not Full, the OSPF configuration between the neighbors is not functioning correctly.