Question: In E-UTRA, what does the "ul-256QAM-r15" field primarily indicate about a User Equipment's (UE) capabilities when reported per component carrier?
Option 1: The UE's support for DL (Downlink) 256QAM in a single band.
Option 2: The UE's capability for voice over LTE (VoLTE) in a specific bandwidth class.
Option 3: The UE's support for UL (Uplink) 256QAM for Multi-Radio Dual Connectivity (MR-DC) within a specified feature set.
Option 4: The UE's maximum power output in a given band combination.
Explanation: This field pertains to the UE's support for Uplink (UL) 256 Quadrature Amplitude Modulation (QAM) specifically in the context of Multi-Radio Dual Connectivity (MR-DC). The other options are incorrect because they misinterpret the direction, technology/application, or capability type.