Question: In a scenario where a UE initiates a fast content switch without an available SDP, and the server responds with a '206 Partial Data' to a PLAY request, what is the primary action the UE takes next regarding transmission resources?
Option 1: The UE waits for the complete SDP file before taking any further actions.
Option 2: The UE modifies an existing transmission resource to accommodate the new content.
Option 3: The UE sets up a new transmission resource, as defined by the addition of media components protocol.
Option 4: The UE sends a repeat request for the complete SDP file before proceeding.
Explanation: When a UE encounters a partial success in content switching without a full SDP, and receives a '206 Partial Data' response, the most appropriate next step is to set up a new transmission resource. This approach ensures the UE can properly handle incoming partial data and prepare for potential receipt of additional media streams or updated session parameters.