What is an Inmarsat "Subscriber Number"?

Correct Answer: Option B — This is the Inmarsat number that is assigned to a unit for incoming calls.

The Inmarsat Subscriber Number, often referred to as the Mobile Earth Station (MES) ID or Inmarsat Number, serves as the unique address for a specific terminal. This identifier is essential for routing incoming calls, data, or messages from the terrestrial network directly to the vessel's satellite terminal.