Router R1, an ASBR connected to the Internet and to backbone area 0, has been configured
with a default-information originate command. Which of the following is true about the effects
of this configuration command?

A.
R1 will always create and flood a default route into the OSPF domain.

B.
R1 will create and flood an LSA for prefix/length 0.0.0.0/0 into the OSPF domain if R1’s IP
routing table has a route to 0.0.0.0/0.

C.
R1 will set a flag on the LSA for the subnet between itself and one of the
ISPs, noting this subnet as a default network, regardless of whether R1 has a default route.

D.
R1 will set a flag on the LSA for the subnet between itself and one of the ISPs, noting this
subnet as a default network, but only if R1 has a route to 0.0.0.0/0.

Explanation:
Without the always parameter, the default-information originate command generates an LSA
for a default route, with prefix 0.0.0.0/0, but only if its own IP routing table has a route for
0.0.0.0/0. It does not flag another LSA as being used as a candidate default route.