Question: What determines a CAG Member Cell for a UE?
Option 1: A cell broadcasting the identity of any PLMN.
Option 2: A cell broadcasting the identity of the selected PLMN, registered PLMN or equivalent PLMN, and for that PLMN, a CAG identifier belonging to the Allowed CAG list of the UE for that PLMN.
Option 3: A cell with a specific PCI value reserved by the network for use by CAG cells.
Option 4: Any cell that is not barred to Rel-15 UEs.
Explanation: According to the principles described, a CAG Member Cell for a UE is specifically determined by the cell broadcasting the identity of the selected PLMN, registered PLMN or equivalent PLMN, and for that PLMN, a CAG identifier belonging to the Allowed CAG list of the UE for that PLMN. This ensures that the UE only considers cells that are part of its allowed CAG list as suitable for connection.