Question: What is the primary purpose of the `SLRB-Uu-ConfigIndex` Information Element in Radio Resource Control (RRC) protocol for 5G New Radio (NR)?
Option 1: To authenticate User Equipment (UE) for security procedures.
Option 2: To identify a sidelink Data Radio Bearer (DRB) configuration from the network side.
Option 3: To manage Quality of Service (QoS) parameters for dedicated bearers.
Option 4: To trigger handover procedures between different base stations.
Explanation: The `SLRB-Uu-ConfigIndex` is used to identify a sidelink DRB configuration, crucial for configuring and managing direct UE-to-UE communication in 5G NR, facilitating services like public safety or vehicle-to-everything (V2X) communications.