A business wants to refresh its legacy Frame Relay WAN and consolidate product specialists via...

B (Layer 3 MPLS VPN hub and spoke):A hub-and-spoke MPLS VPN allows scalable branch-to-data-center communication with efficient routing, simplified management, and adequate support for real-time video across 200 branches.

Other options explained:

A: DMVPN is flexible but not as scalable or deterministic for 200-site enterprise video conferencing.

C: VPLS operates at Layer 2 and may introduce unnecessary broadcast domain scaling challenges.

D: Full mesh MPLS is difficult to manage for such a large number of sites.