Question: In UTRAN Iu interface RANAP signalling, what does the Cell Load Information IE primarily convey for a specific cell (serving or target), as per RNC's support for cell load-based inter-system handover?
Option 1: The cell's current and projected power capacity for both Downlink and Uplink.
Option 2: The cell's geographical coverage area and neighboring cell IDs.
Option 3: The cell's subscriber count and active call volume at a given time.
Option 4: The current traffic load in the cell (or assumed load post-handover) for either Downlink or Uplink.
Explanation: This is correct because the Cell Load Information IE contains the load information of a specific cell for either the Downlink or the Uplink, reflecting the current traffic load (or the assumed load after a successful handover), which impacts cell load-based inter-system handover decisions and network resource allocation.