試題詳解

4. What sound signals should a vessel engaged in fishing, sound in reduced visibility?
(A) One prolonged followed by two short blasts at intervals of not more than 2 minutes.
(B) One prolonged blast at intervals of not more than 2 minutes.
(C) Two prolonged blasts at intervals of not more than 2 minutes.
(D) Four short blasts at intervals of not more than 2 minutes.