Which statement is true about the area-range command?

Which statement is true about the area-range command?

A.
When the area-range command is used, the ABR generates a default route.

B.
You can have only one area-range statement per OSPF area.

C.
The area-range command can only be used to summarize internal routes.

D.
The area-range statement can be configured under an NSSA area to summarize external routes.