单项选择题
A.a pipe with welded connections B.a pipe with several clips C.a cement box D.a leaking valve
A.make his decision independently B.request the owner’s representative to provide proposals C.cooperate with the flag State Administration’s representatives D.consult the organization responsible for issuing the relevant certificates
A.prevent an unsafe ship proceeding to sea B.prevent a ship threatening the marine environment C.fine the ships D.confirm a safe sailing