The command output in the exhibit provides direct information about the signaling and discovery mechanisms for MVPN service 100. The line C-Mcast Signaling: BGP indicates that BGP is used to exchange customer multicast routing information (C-flows) between Provider Edge (PE) routers. The line Auto-discovery: BGP indicates that BGP is also used for the discovery of other PEs participating in the same MVPN instance. This architecture is characteristic of Next-Generation MVPN (NG-MVPN), where BGP extensions handle both PE auto-discovery and the signaling of customer multicast state, replacing the need for PIM in the provider core for these functions.

A. This is incorrect. The exhibit clearly shows Auto-discovery: BGP, meaning BGP, not PIM, is used to discover PEs.

B. This is incorrect. The exhibit explicitly states C-Mcast Signaling: BGP, meaning BGP, not PIM, is used for customer multicast signaling.

D. This is incorrect. The exhibit shows that BGP is used for both functions, not PIM. PIM may be used within the customer network (C-PIM), but not for signaling or discovery between PEs in this configuration.

1. Nokia 7750 SR and 7450 ESS Services Guide, Release 21.10.R1, Document Part Number: 3HE 17661 AAAC TQZZA, Section: BGP-Based MVPN.

This section details the NG-MVPN architecture, stating, "BGP is used for auto-discovery and to transport C-multicast routing information." It further explains that BGP auto-discovery routes are used for PE discovery and BGP C-multicast routes are used to signal C-multicast information. The fields C-Mcast Signaling and Auto-discovery in the show service id mvpn command output directly correspond to these functions.

2. Nokia 7750 SR and 7450 ESS Services Guide, Release 21.10.R1, Document Part Number: 3HE 17661 AAAC TQZZA, Section: MVPN Command Reference, show service id mvpn command.

The documentation for this command describes the output fields. It specifies that C-Mcast Signaling displays the protocol used to signal customer multicast information (BGP or PIM) and Auto-discovery displays the protocol used for PE auto-discovery (BGP or PIM). The exhibit's output of "BGP" for both fields confirms the scenario in the correct answer.