Explanation: The international auto-alarm signal is a specific sequence of alternating two-tone transmissions designed to activate automatic alarms on ships, alerting watchstanders to an impending distress message. A crucial waiting period is prescribed between the auto-alarm signal and the actual distress call (MAYDAY). This 2-minute delay allows sufficient time for the automatic alarm equipment to reliably detect the signal, activate the ship's alarm, and for personnel to respond to the alarm and prepare to receive the critical distress message. This interval is an internationally standardized maritime communication protocol to ensure distress calls are received effectively. Waiting for longer periods, as suggested by options B, C, or D, would unduly delay the transmission of vital distress information, potentially endangering lives or assets.