Question: What is the primary purpose of measuring 'Failed RRC Connection Establishment per Failure Cause' in an Evolved Universal Terrestrial Radio Access Network (E-UTRAN)?
Option 1: To optimize handover procedures between eNodeBs
Option 2: To support Load Balancing Optimization (LBO) target setting and evaluation
Option 3: To enhance Quality of Service (QoS) for voice services in EPS
Option 4: To troubleshoot RRCConnectionReject messages caused by Energy Saving modes
Explanation: The correct answer aligns with the context, highlighting the importance of understanding failed RRC connections to optimize network load distribution in E-UTRAN for efficient resource utilization. The other options, while related to telecom concepts, do not directly match the primary purpose outlined for this specific measurement.