006C D
 Which of the following is a requirement, under GMDSS, for all vessels over 300 gross tons operating within range of a MF-DSC equipped shore station?
a) Ship's Master or radio officer must be on duty at all times.
b) At least 2nd class Telegraphy license or GMDSS Element 9 is required for the radio officer.
c) Spare parts and maintenance kit for repairs.
d) Only one of the three maintenance options is required.
