Which OSPF LSA type does an ASBR use to originate a default route into an area？（）

A.IP prefix
B.Layer 2 circuit
C.RSVP request from CE for bandwidth reservation
D.BGP MED value

A.They are used to summarize area routes to other areas.
B.They are used in not-so-stubby areas to propagate external routes.
C.They are used to notify areas of the ASBR.
D.They are flooded to all areas except stub areas （external route）.

A.The Layer 2 multicast address of the destination node
B.The solicited node multicast address of the destination node
C.The Layer 2 address of the destination node based on the destination IPv6 address
D.The IPv6 address of the destination node based on the destination Layer 2 address