Question: In a handover scenario from UTRAN FDD to E-UTRAN TDD, what marks the starting point for measuring the handover delay in a combined UTRAN FDD and E-UTRAN TDD UE?
Option 1: Reception of the first TTI on the new E-UTRAN TDD channel
Option 2: Transmission of the last TTI containing an RRC message implying hard handover
Option 3: End of the last TTI containing an RRC message implying hard handover
Option 4: Initiation of the handover request by the User Equipment (UE)
Explanation: The correct answer marks the moment when the UE is instructed to switch, and the delay is then measured until transmission begins on the new channel (E-UTRAN TDD), crucial for evaluating inter-RAT handover performance in telecom networks involving UTRAN and E-UTRAN technologies.