Question: What triggers the measurement of successful outgoing handovers when Discontinuous Reception (DRX) is not used in an Evolved Universal Terrestrial Radio Access Network (E-UTRAN)?
Option 1: Receipt of a RRC message RRCConnectionReconfigurationComplete sent from the UE to the target eNB, indicating a successful incoming intra-eNB handover.
Option 2: Receipt at the source eNB of UE CONTEXT RELEASE over the X2 from the target eNB following an unsuccessful handover when DRX is used.
Option 3: Receipt of a RRC message RRCConnectionReconfigurationComplete sent from the UE to the target (=source) eNB, indicating a successful outgoing intra-eNB handover when DRX is not used.
Option 4: Receipt at the source eNB of UE CONTEXT RELEASE COMMAND following an unsuccessful handover when DRX is not used.
Explanation: The correct answer is Option 3 because it accurately describes one of the triggers for measuring successful outgoing handovers without using DRX, as specified in the context. This option correctly identifies the receipt of a specific RRC message indicating a successful outgoing intra-eNB handover when DRX is not used.