Explanation: Proper watchkeeping, especially in the context of the Global Maritime Distress and Safety System (GMDSS), is multifaceted and critical for maritime safety. Maintaining a proper GMDSS radio station log is a fundamental regulatory requirement. This log documents all communications, distress alerts, safety broadcasts received, and equipment tests, providing a crucial record of events. Understanding normal operational indicators allows the watchstander to quickly identify malfunctions or deviations from expected performance, ensuring equipment readiness for distress or safety situations. Responding to and comprehending alarms is paramount. Alarms from DSC, EPIRBs, SARTs, or other GMDSS equipment signify potential distress or urgent safety information. A prompt and correct response is essential to initiate or assist in rescue operations. Options A and D are incorrect because "setting the DSC scanner frequencies to minimize alarms" would entail disabling critical monitoring, potentially missing distress alerts, which is contrary to safety regulations. Option C is incorrect as "logging out of Inmarsat-C terminals while at sea" would prevent the reception of vital safety information via SafetyNET or distress alerts.