单项选择题

A.RouterAmusthaveaLevel2adjacencywiththeLevel1/Level2routerinarea49.0001.
B.TheLevel1/Level2routerinarea49.0001setsthe"attached"bitintheLevel2LSPitfloodsintoarea49.0001.
C.TheLevel1/Level2routerinarea49.0001setsthe"attached"bitintheLevel1link-statePDU(LSP)itfloodsintoarea49.0001.
D.TheLevel1/Level2routerinarea49.0001advertisestheseprefixedintoarea49.0001usingaLevel2LSPitfloodsintothearea.