Question: In UTRAN's Iur interface, what happens to Mac-d flows from each carrier when Multi-Carrier E-DCH Transport Bearer Mode LCR is set to 'E-DCH UL flow multiplexing mode'?
Option 1: Each carrier's Mac-d flow is transmitted over a shared Iur transport bearer but with prioritized scheduling.
Option 2: The Mac-d flows received on different carriers in the DRNS are multiplexed onto one Iur transport bearer.
Option 3: Carriers with lower signal strength use a separate Iur transport bearer, while stronger signals share one.
Option 4: All Mac-d flows are routed through a single carrier before being transmitted over one Iur transport bearer.
Explanation: This is the correct behavior for 'E-DCH UL flow multiplexing mode', where multiple carriers' Mac-d flows are combined (multiplexed) onto a single Iur transport bearer in the DRNS, optimizing resource utilization by consolidating traffic from multiple carriers into one bearer.