Question: What is a key responsibility of an MCData Server performing the Controlling Role in a one-to-one or group data communication, specifically regarding transmission and reception?
Option 1: Handling authorization for participation in the MCData group communication towards all MCData users.
Option 2: Managing SDS and FD data distribution during MCData group communication.
Option 3: Interfacing exclusively with the SIP AS functional entity of the signalling control plane.
Option 4: Relaying MCData communication messages between MCData clients without storing any data.
Explanation: An MCData Server in the Controlling Role is responsible for handling transmission and reception control, which includes policy enforcement for participation in the MCData group communication towards all the MCData users of the one-to-one and group data communication. This encompasses authorization aspects, making Option 1 the correct answer.