Which three statements about IS-IS are true? (Choose three.)
A.
L1 routers have no knowledge about routes outside their area.
B.
L1/L2 routers maintain a separate Level 1 link-state database and a Level 2 link-state database;
they do not advertise L2 routes to L1 routers.
C.
To route packets to another area, L1 routers must forward the packets to the L2 router of the
destination area.
D.
To route packets to another area, L1 routers must forward the packets to an L1/L2 router within
their area.
E.
L2 routers form adjacencies with L1 and L1/L2 neighbors.