7-90J2 A
 During SITOR (NBDP) ARQ operations through a coast station, what should the GMDSS operator do during the "Automatic Exchange of Answerbacks"?
A. Do nothing other than wait for a GA+? prompt and then issue the desired command.
B. Send a "WRU" then a "Here is" when requested to do so by the coast station.
C. Send the necessary message file and then wait for time and charges.
D. Wait for the coast station to transmit a menu of possible commands and select the desired action.
