If you are sending communications to a fax machine on a vessel's Inmarsat-B terminal in the AOR-E, which entry is formatted correctly?

In the context of sending communications to a fax machine using an Inmarsat-B terminal in the Atlantic Ocean Region-East (AOR-E), the format of the entry must adhere to the specific structure used for fax services. Inmarsat systems utilize Mobile Satellite Services (MSS), and the identifiers used for mobile phones or other devices typically begin with specific country or service codes.

The correct answer adheres to the established number format for Inmarsat communications, where the number begins with the prefix that is designated for mobile satellite communications. The prefix "870" signifies that the number is associated with Inmarsat's mobile services, making it the appropriate choice for fax machines using this satellite communication system.

In contrast, the other options do not start with the "870" prefix, which is critical for identifying them as satellite service numbers. Therefore, the correct number format that aligns with the requirements for faxing communications through Inmarsat-B in the AOR-E is represented by the entry that starts with "870".