A vessel has a charter party for one voyage to carry a full load of manganese from Durban，South Africa，to Baltimore，Maryland，at a stipulated rate per ton. Which type of contract is involved? （）

A.moderating winds and heavy confused seas to strike his vessel from all directions
B.the winds to increase to hurricane force and strike from a different direction as the eye passes
C.the barometer to reach the lowest point
D.All of the above

A.an anchor light
B.sidelights and a stern light
C.three lights in a vertical line，the highest and lowest being red，and the middle being white
D.None of the above

A.restricted in her ability to maneuver
B.not under command
C.engaged in mineclearing operations
D.constrained by her draft