Once ARQ communication with the coast radio station has been established, which of the following exchanges will most likely take place?

Correct Answer: Option C — After exchanging answer-backs (WRU-AAB) with the vessel, the coast radio station transmits GA+?.

Once an ARQ link is established, the stations exchange answer-backs (WRU-AAB) to confirm identity. Following this, the coast station sends 'GA+?' (Go Ahead), signaling that the system is ready for the vessel to transmit its message or subscriber information, standardizing the automated telex workflow for maritime traffic.