Question: What is a prerequisite for a User Equipment (UE) to support 14 DL HARQ processes with HARQ-ACK delay solution Alt-1 in FDD, when operating in coverage enhancement mode A?
Option 1: The UE must also support ce-ModeA-r13.
Option 2: The UE needs to operate exclusively in TDD mode.
Option 3: The UE has to be capable of up to 16QAM modulation only.
Option 4: The UE should have a minimum of 4 receive antennas.
Explanation: According to the specifications, for a UE to support 14 DL HARQ processes with HARQ-ACK delay solution Alt-1 in FDD when in coverage enhancement mode A, it is mandatory that the UE also indicates support for ce-ModeA-r13. This ensures compatibility and proper functioning of the enhanced features within the specified mode.