An engineer must configure Cisco IM & Presence services on Cisco Unified CM for Jabber under the Expressway Domain. Which accomplishes this task?

When Jabber clients use Expressway for Mobile and Remote Access (MRA), enabling 'SIP registrations and provisioning on Expressway' allows Expressway to handle SIP registration and UDS provisioning requests from Jabber clients. This setting is required for IM and Presence services to be reachable over the Expressway path, as it instructs the system to route Jabber registration and configuration requests through the Expressway-C and Expressway-E infrastructure.

Setting this option to Off disables Expressway handling of Jabber SIP registrations and provisioning, which would prevent IM and Presence services from functioning for MRA clients.

Enabling IM and Presence services on Cisco Unified CM addresses internal client connectivity but does not configure the Expressway domain path required for this specific scenario.

Disabling IM and Presence services on Cisco Unified CM would break IM and Presence functionality for all Jabber clients, including internal users.