Question: For a User Equipment (UE) supporting Rel-15 V2X sidelink communication, what is the requirement regarding rate matching and TBS scaling for V2X sidelink communication as per 3GPP specifications?
Option 1: Optional support for rate matching but mandatory support for TBS scaling.
Option 2: Mandatory support only for rate matching, with TBS scaling being optional.
Option 3: Support for both is entirely optional for all UEs.
Option 4: Mandatory support for both rate matching and TBS scaling.
Explanation: According to the specifications, for UEs that support Rel-15 V2X sidelink communication, it is mandatory to support both rate matching and TBS (Transport Block Size) scaling for efficient V2X sidelink communication. This ensures all such UEs can effectively manage data transmission rates in vehicle-to-everything (V2X) scenarios, aligning with the reliability and performance requirements of V2X services.