Question: What is the purpose of the Wake Up Signal (WUS) feature in the 5G System, and how does it reduce UE's idle mode power consumption?
Option 1: The WUS feature allows UEs to determine their location and adjust their transmission power accordingly.
Option 2: The WUS feature enables UEs to switch to a different radio access technology (RAT) to reduce power consumption.
Option 3: The WUS feature allows the RAN to notify UEs shortly before their paging occasion, enabling them to wake up only when necessary and reducing idle mode power consumption.
Option 4: The WUS feature enables UEs to transmit data during their idle mode, increasing their power consumption.
Explanation: The correct answer is Option 3 because the WUS feature allows the RAN to notify UEs shortly before their paging occasion, enabling them to wake up only when necessary and reducing idle mode power consumption. This is stated in the text as "The RAN sends the WUS shortly before the UE's paging occasion." This feature helps reduce the UE's idle mode power consumption by avoiding unnecessary wake-ups.