Which of the following statements concerning SITOR communications is true?

Correct Answer: Option C — FEC transmissions rely upon an error correction technique, which transmits each character twice.

FEC mode operates by transmitting each character twice in a time-delayed sequence. The receiver compares the two versions; if the first is corrupted, it uses the second to reconstruct the data. This method provides error correction for one-way broadcasts where no return channel exists for requesting repeats.