Which mode of communication is possible through an Inmarsat-C SES?

Correct Answer: Option B — TELEX and e-mail

Inmarsat-C operates as a digital messaging terminal. It is designed to handle text-based communications such as TELEX and e-mail. It does not support analog voice (radiotelephone), SITOR (which is an HF radio protocol), or DSC (which is a VHF/MF/HF radio signaling protocol) for its primary communication path.