Explanation:

Box 1: Azure Traffic Manager
Traffic Manager is a DNS-based traffic load balancer that enables you to distribute traffic optimally to services across global Azure regions, while providing high availability and responsiveness. Because Traffic Manager is a DNS-based load-balancing service, it load balances only at the domain level. For that reason, it can't fail over as quickly as Front Door, because of common challenges around DNS caching and systems not honoring DNS TTLs.

Reference:
https://docs.microsoft.com/en-us/azure/architecture/guide/technology-choices/load-balancing-overview