Question: What is a prerequisite for a User Equipment (UE) to support the 'aul-r15' feature, as related to Autonomous Uplink in Evolved Universal Terrestrial Radio Access (E-UTRA)?
Option 1: The UE must support uplink Low-Density Parity-Check (LDPC) coding.
Option 2: The UE must support downlink 256QAM modulation.
Option 3: The UE must support uplink Licensed Assisted Access (LAA) operation.
Option 4: The UE must have a minimum of two transmit antennas.
Explanation: The correct answer is Option 3 because the 'aul-r15' feature's applicability depends on the UE supporting uplink Licensed Assisted Access (LAA) operation, indicating a direct dependency between uplink LAA support and Autonomous Uplink features like 'aul-r15'.