Which two statements about classful or classless routing protocol operations are true?
(Choose two.)

A.
Classful routing protocols do not send subnet mask information with their

B.
routing updates.
Variable-length subnet masks are supported when using classful routing protocols.

C.
Examples of classless routing protocols include RIPv1, EIGRP, OSPF, and IS-IS.

D.
Classful routing protocols do not support discontiguous subnets.