27D1 C
 Which of the following statements concerning DSC equipment is true?
A. The GMDSS Radio Operator is not responsible for properly selecting HF DSC guard channels because they are done automatically by the watch receiver.
B. All equipment must be type accepted by Inmarsat.
C. The vessel's navigational position must be updated, either automatically or manually, no less often than every four (4) hours.
D. The GMDSS Radio Operator is responsible for properly selecting VHF & MF DSC guard channels but the HF frequencies are done automatically by the watch receiver.
