Refer to the exhibit.

The correct configuration for MPLS LDP synchronization with OSPF process 1 on router R1 is to use the command mpls ldp igp sync holddown 60 under the OSPF process configuration. This ensures that the MPLS LDP synchronization is enabled and held for 60 seconds with OSPF process 1, which helps prevent black holes in MPLS networks during the convergence process by ensuring that routes are not advertised until LDP is fully operational and labels have been exchanged between adjacent routers.

References:

Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) - Cisco SPCOR

Additional resources on Cisco’s Service Provider training: Cisco Service Provider Training