A.Manually assign RID
B.Configure local-address
C.Enable the fxp0 interface
D.Assign nonmartian address to lo0.

A.Import policies are not allowed， so this is not possible.
B.Export policies are not allowed， so this not possible.
C.Apply a firewall filter matching 10.0.0./4/30 and reject the route.
D.Apply an import policy matching 10.0.0.4/30 and reject the route.

A.It describes the reachability of routes in stub areas.
B.It describes the reachability of routes in totally-stubby areas.
C.It describes the reachability of routes in not-so-stubby areas.
D.It describes the reachability of routes in partially-stubby areas.

A.MD5
B.DES
C.Kerberos
D.Unauthenticated
E.Simple password

A.AF
B.AFI
C.MAC
D.Area
E.SysID
F.A-Selector
G.N-Selector
H.IP-address

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.

A.broadcast hellos
B.Level 1 LAN hellos
C.Point-to-point hellos
D.Level 2 point-to-point hellos

A.route filtering
B.protect the routing engine
C.securing the router control plane
D.protect against hidden bridge loops
E.protect against denial of service attacks