The basic concept of GMDSS is（）.
- ASearch and rescue authorities ashore will rapidly received an distress alert and acted upon
- BSAR units will be rapidly alerted to a distress incident and assist in a coordinated SAR operation
- CShips navigating in the immediate vicinity of the ship in distress will rapidly alerted to the alert and give their help accordingly
- DThe RCC will rapidly alerted to a distress alert through satellite and terrestrial communication techniques and conducted a rescue operation immediately