What action should be taken on changing from one ocean region to another?

Correct Answer: Option C — Log out of the current satellite and log in to the correct satellite.

When transitioning between satellite footprints, the terminal must be explicitly reconfigured. Logging out of the current satellite ensures the network updates the vessel's status, while logging into the new satellite establishes the necessary link for continued GMDSS watchkeeping and data reception in the new ocean region.