A.The TTL field from the IP packet is copied into the TTL field of the MPLS label header at the ingress edge LSR
B.TTL propagation cannot be disabled in an MPLS domain
C.TTL propagation is only disabled on the ingress edge LSR
D.The TTL field of the MPLS label header is set to 255
E.The TTL field of the IP packet is set to 0