What is defined as the area within the radiotelephone coverage area of at least one VHF coast station in which continuous DSC alerting is available as defined by the IMO regulation for GMDSS?

Correct Answer: Option A — Sea Area A1

Sea Area A1 is defined as the area within the radiotelephone coverage of at least one VHF coast station in which continuous DSC alerting is available. This typically extends 20 to 30 nautical miles from the coast, ensuring reliable distress alerting via VHF Channel 70 for vessels in coastal waters.