How do routers in an IS-IS Level-1 domain exit to reach other Level-1 domains? (Choose two.)

A.
Level-1 routers use default routes announced by Level-2 routers in Level-1 domain

B.
Level-1 routers use default routes installed based on ATT bit (Attach Bit) in announcements
from Level-1-2 router

C.
Level-1 routers use specific routes, for other Level-1 domain, announced by Level-1-2 router by
route leaking feature of Cisco IOS

D.
Level-1 routers use specific routes, for other Level-1 domain, announced by Level-2 router by
route-leaking feature of Cisco IOS