**An engineer is troubleshooting L3VPN traffic loss over the MPLS-enabled core network when new core links were enabled. Assuming that the IGP is properly configured, which issue causes a temporary data flow blackholing when the IGP and LDP reconvenes?
A. LDP is a Layer 2 protocol forwarding label packets before the IGP reconvened.
B. IP packets are forwarded as soon as routes are learned over a new IGP adjacency before the label exchange happens over the new links
C. MP-BGP sessions between PE and RR routers require extra time to reconverge than the underlying IGP.
D. MPLS-TE tunnels without LDP adjacencies are used over the new links black-holing the traffic before the LDP label exchange is completed
