What is the frequency range for High Frequency?

Correct Answer: Option A — 3-30 MHz

High Frequency (HF) radio spectrum is defined by the ITU as the range from 3 MHz to 30 MHz. This band utilizes skywave propagation, allowing for long-range, over-the-horizon communication, which is essential for GMDSS distress alerting and safety traffic when vessels are operating outside of satellite or VHF coverage.