Explanation: To determine if a distress situation is genuine, direct communication is paramount. After an initial distress call is made on a designated distress frequency (like VHF Ch 16), stations involved are instructed to shift to a *follow-on working frequency* to conduct the actual, detailed communications. Monitoring these voice communications allows you to hear the specifics of the situation, the urgency, and potentially interact with the distressed vessel or assisting stations. This direct, real-time exchange is the most effective way to ascertain the genuineness and nature of the emergency, providing context and confirmation that other methods cannot. Options A (SART) and B (EPIRB) are automated distress signals that indicate an emergency and provide location data. While crucial, they don't offer the interactive communication needed to verify the situation's genuineness directly. Option C (NAVTEX) broadcasts confirmed information from authorities but is a secondary report, not a direct method for you to verify the distress firsthand.