A.0 B.1 C.2 D.3
A.Sending out a graceful restart PDU B.Sending an LSP that contains no TLVs. C.Sending out a restarts TLV with the RR bit set. D.Reflooding its LSP with a maximum sequence number.
A.Router A must have a Level 2 adjacency with the Level 1/Level 2 router in area 49.0001. B.The Level 1/Level 2 router in area 49.0001 sets the "attached" bit in the Level 2 LSP it floods into area 49.0001. C.The Level 1/Level 2 router in area 49.0001 sets the "attached" bit in the Level 1 link-state PDU (LSP) it floods into area 49.0001. D.The Level 1/Level 2 router in area 49.0001 advertises these prefixed into area 49.0001 using a Level 2 LSP it floods into the area.