Explanation: DSC Distress alerts are designed to be transmitted directly by the distressed vessel to Coast Stations and other vessels. The GMDSS system uses automated acknowledgment to confirm receipt of these alerts. Relaying a DSC Distress alert should only be performed under specific circumstances, such as when the original alert has not been acknowledged by a Coast Station after a reasonable period (typically 5 minutes), or if there is clear evidence that the original transmission failed. Indiscriminate or immediate relaying by other vessels can quickly overburden the DSC calling channels (e.g., VHF Ch. 70). This creates redundant traffic, clogs the system, and can make it more difficult for Coast Stations to identify the original distress signal, process acknowledgments, and coordinate rescue efforts effectively. Therefore, option D is correct because inappropriate relaying can lead to system congestion and confusion. Options A, B, and C are incorrect because relaying is a secondary, conditional measure, not the primary or immediately preferred method for initial notification or confirmation of an alert.