Prior to being able to sail in a US port，each vessel that carries grain in bulk must have a certificate of loading issued by the（）.

A.Empty double-bottoms and lower holds，and a heavy deck cargo
B.Flooding the forepeak to correct the vessel's trim
C.Having KG smaller than KM
D.Having a small positive righting arm

A.cargo which occupies a large volume of space
B.cargo which requires refrigeration
C.cargo which is very dense
D.homogeneous cargo not enclosed in a container

A.determine the cause before taking countermeasures
B.assume the shift is due to off-center loading
C.counterflood on the side opposite the list or trim
D.assume the cause is environmental forces