Question: In a UTRAN to E-UTRAN cell handover scenario, what marks the starting point for measuring the handover delay in a UTRA FDD UE that supports inter-RAT PS handover to E-UTRA (FDD)?
Option 1: The moment the UE receives the first TTI from the new E-UTRAN cell.
Option 2: The end of the last Transmission Time Interval (TTI) containing an RRC message implying handover.
Option 3: The initiation of the handover procedure by the UTRAN network.
Option 4: The successful establishment of the RRC connection on the new E-UTRAN cell.
Explanation: According to specifications for measuring handover delay in scenarios involving a switch from UTRAN to E-UTRAN, the starting point is specifically defined as the end of the last Transmission Time Interval (TTI) that contains an RRC message which implies the handover, marking the transition initiation from one radio access technology (RAT) to another.