单项选择题
A.for 1 year
B.for 2 years
C.until the next Coast Guard inspection
D.until the vessel's Certificate of Inspection expires
单项选择题 Port of Registry refers to the port where（）.
单项选择题 On vessels over 100 gross tons，whose responsibility is it to ensure that all able seamen in the vessel’s crew have the documents and qualifications required by law and regulation?（）
单项选择题 Official proof of an American vessel’s nationality is contained in the（）.