Which statement about OSPF loop prevention is true?
A.
The discard route is generated automatically on the ABR to prevent routing loops.
B.
The ASBR uses type 3 LSAs from non-backbone areas to prevent control-plane routing loops.
C.
The ABR can filter type 3 LSPs to prevent routing loops.
D.
The DN bit ignores LSA types 2, 3, and 5 to prevent routing loops.
A is corrrect.
But C also relevant but if replace “cat” to “must”, because ABR discard LSA3 received from neighbor from non-area 0.