Explanation: Proper procedures for distress situations under GMDSS (Global Maritime Distress and Safety System) are mandated by regulations, not equipment-specific manuals. **47 CFR Part 80 Subpart W** is the correct source. Title 47 of the Code of Federal Regulations deals with Telecommunication. Part 80 specifically governs "Stations in the Maritime Services," and Subpart W is dedicated to the "Global Maritime Distress and Safety System (GMDSS)." This subpart outlines the operational and procedural requirements for GMDSS, including distress communications. Manufacturer's technical (A) and operator (B) manuals are essential for understanding how to use specific GMDSS equipment, but they do not define the overarching regulatory procedures and protocols for distress situations. Those are established by national and international regulations. **47 CFR Part 90 Subpart V** is incorrect because Part 90 covers "Private Land Mobile Radio Services," which is entirely unrelated to maritime operations and GMDSS.