Question: In a cell offering both E-UTRA connectivity to 5GC and EPC within the same Public Land Mobile Network (PLMN), what layer is responsible for indicating the selected Core Network (CN) type during the PLMN selection procedure?
Option 1: UE Application Layer (AS)
Option 2: UE Non-Access Stratum (NAS) Layer
Option 3: UE Access Stratum (AS) Layer for CN type indication, but NAS for PLMN selection
Option 4: Radio Resource Control (RRC) Layer
Explanation: The correct answer is the UE Non-Access Stratum (NAS) Layer. This is because the NAS layer, which handles core network-related signaling, is responsible for indicating the selected CN type (if available) along with the selected PLMN during the PLMN selection procedure. The AS layer does play a role in indicating available CN types to upper layers but not in confirming the selection during the PLMN selection process.