Which of the following can either directly or indirectly identify all the interfaces for which both
1) OSPF has been enabled and 2) OSPF is not passive? (Choose two.)

A.
show ip ospf database

B.
show ip ospf interface brief

C.
show ip protocols

D.
show ip route ospf

E.
show ip ospf neighbors

Explanation:
First, for the two correct answers: show ip ospf interface brief explicitly
lists all OSPF-enabled interfaces that are not passivE. show ip protocols lists either
the details of the configured network commands, or if configured using the ip ospf
area command, it lists the interfaces on which OSPF is enableD. This command also
lists the passive interfaces, so armed with interface IP address information, the list of
OSPF-enabled nonpassive interfaces could be deriveD. Of the three wrong answers,
show ip ospf database does not list enough detail to show the OSPF-enabled interfaces.
show ip route ospf lists only routes learned with OSPF, so if no routes use a
particular OSPF-enabled interface as an outgoing interface, this command would not
indirectly identify the interface. Finally, an interface may be OSPF-enabled but with

no neighbors reachable on the interface, so the show ip ospf neighbor command may not
identify all OSPF-enabled interfaces.