Question: Where is Radio Bearer Control (RBC) primarily located in the Evolved Universal Terrestrial Radio Access Network (E-UTRAN) architecture?
Option 1: User Equipment (UE)
Option 2: Evolved Node B (eNB)
Option 3: Mobility Management Entity (MME)
Option 4: Serving and Packet Data Network Gateway (S/PGW)
Explanation: Radio Bearer Control (RBC) is crucial for managing radio resources in E-UTRAN, including setup, maintenance, and release of radio bearers based on network resource situations and Quality of Service (QoS) requirements. Given its functions, RBC needs direct access to and control over the radio resources, making the Evolved Node B (eNB), which manages the radio interface, the most logical location for RBC. This ensures efficient allocation and deallocation of radio resources in real-time, aligning with the eNB's role in controlling the radio access network.