Which of the following is a correctly formatted Inmarsat-B address for sending communications to a shoreside TELEX terminal number 440122 in the United Kingdom?

The correct formatting for an Inmarsat-B address sending communications to a shoreside TELEX terminal involves specific conventions. The number should start with a 5, which designates it as a TELEX number. Following this, the desired TELEX terminal number is included.

In the case of the United Kingdom, TELEX numbers typically follow this pattern where the address consists of the country code and the TELEX number itself without any additional symbols or modifications. The last character can vary to indicate the end of the address; using a plus sign is a valid choice here as it signifies that the message should be forwarded and appears commonly in such telecommunications formats for clarity in routing.

The option that includes the "51440122+" aligns with this standard; it clearly denotes the TELEX code "440122" as a valid destination in the UK within the Inmarsat system. The plus sign at the end indicates it is the end of the address, accommodating the communication protocols for message handling.

Other options do not follow this formatting correctly. For instance, options with symbols like "#" or parentheses are either non-standard or suggest alternate usage that is not recognized within the established Inmarsat-B addressing conventions.