Which component allows Cisco Jabber to communicate with clients who are outside the corporate network?

Cisco Extension Mobility allows users to temporarily log in to a shared Cisco IP phone at a different desk, not to enable remote external access.

Cisco TMS (Telepresence Management Suite) is a scheduling and management platform for video conferencing systems, unrelated to Jabber remote access.

Cisco Mobility Remote Destination is a feature used with Single Number Reach to ring a mobile phone simultaneously, not to proxy Jabber traffic from outside the network.

Cisco Unified RTMT (Real-Time Monitoring Tool) is a diagnostic and monitoring application for UC infrastructure, not a connectivity component for remote clients.

Cisco Mobile and Remote Access (MRA) is the feature that allows Cisco Jabber clients located outside the corporate network to securely register and communicate with internal Cisco Unified CM services. MRA is implemented via a Cisco Expressway-E and Expressway-C pair, which proxies SIP, media, and XMPP traffic without requiring a VPN connection from the end user.