A signal of one prolonged，one short，one prolonged，and one short blast，in that order is given by a vessel（）.

A.a vessel meeting another head-on
B.a vessel overtaking another in a narrow channel
C.a vessel crossing the course of another
D.the give-way vessel in a crossing situation

A.power-driven vessel following a traffic lane
B.pilot vessel enroute to a pilot station
C.law enforcement vessel
D.All of the above

A.stand-on vessel and would sound two short blasts
B.give-way vessel and would sound no whistle signal
C.stand-on vessel and would sound no whistle signal
D.give-way vessel and would sound two prolonged blasts followed by two short blasts