A voice engineer is setting up Cisco Jabber IM and must provide visibility for users not on their contact list Which feature must be enabled to allow this visibility?

Availability Sharing controls how a user publishes and shares their own presence status with others and does not grant visibility into non-contact users' presence.

Ad-Hoc Presence Subscription is a feature configured in CUCM that allows Jabber clients to dynamically subscribe to the presence of any user in the directory, not just those explicitly added as contacts. When this feature is enabled, a user can see the availability status of colleagues they have not formally added, providing broader visibility across the organization.

Offline Messaging enables the delivery of instant messages to users who are currently offline and is unrelated to presence visibility for non-contact users.

Instant Messaging is the general text messaging capability of Jabber and does not specifically control or enable presence visibility for users outside a contact list.