Which of the following would indicate an Inmarsat-B terminal?

An Inmarsat-B terminal is characterized by its unique identification number, which is a 9-digit format. The correct identification for these terminals starts with the digit “3.” This specific prefix is vital as it distinguishes Inmarsat-B from other types of terminals within the Inmarsat system, ensuring that communications, accounting, and service functions are properly allocated to the correct satellite service.

The choice referring to a 9-digit number beginning with the MID could be misleading because the MID (Maritime Identification Digits) does not specifically identify Inmarsat-B terminals. Also, a 7-digit number does not fit the structure for identifying these terminals, as Inmarsat-B requires that 9-digit formulation. Lastly, an option detailing a 9-digit number starting with 4 would not apply to Inmarsat-B, as this range of starting digits does not correspond to the identified subset of terminals associated specifically with Inmarsat-B service.

Thus, the identification of an Inmarsat-B terminal by a 9-digit number beginning with the digit 3 is essential for accurate and efficient satellite communication in maritime operations.