A customer requests a configuration that enables users to easily add a third party to an existing call. The environment contains only three Cisco TelePresence C40 codecs and one Cisco VCS. To achieve the customer's requirements, which feature should be added?

A.	Cisco MultiWay
B.	Cisco TelePresence Conductor
C.	Cisco TMS
D.	Cisco Multisite
E.	Cisco VCS Expressway