38E4 C
 GMDSS vessels equipped for Sea Areas A2, A3 or A4 must maintain a continuous DSC watch on 2187.5 kHz.
A. Only in areas beyond Inmarsat coverage.
B. Only outside of areas covered by VHF-DSC.
C. At all times when underway.
D. When directed to do so by a cognizant rescue authority.
