Question: What indicates a successful outgoing intra-frequency handover in an E-UTRAN network?
Option 1: Receipt of a RRC message RRCConnectionReconfigurationComplete sent from the UE to the target eNB/RN.
Option 2: Receipt of a S1AP message HandoverCancel at the source eNB following an unsuccessful inter-eNB intra-frequency handover.
Option 3: Receipt of a NAS message AttachAccept at the MME following a successful initial attach procedure.
Option 4: Receipt of a BSSMAP message ClearRequest at the MSC following a successful inter-MSC handover.
Explanation: A successful outgoing intra-frequency handover in an E-UTRAN network is indicated by the receipt of a RRC message RRCConnectionReconfigurationComplete sent from the UE to the target eNB/RN, as specified in TS 36.331. This message confirms that the handover has been successfully completed and the UE has reconfigured its radio resources accordingly.