It should be noted（）the use of synthetic mooring ropes able to produce sparks by their manipulation is absolutely forbidden on board petroleum tankers and LPG or LNG carriers, or any vessel carrying inflammable substances.

A.that

B.which

C.who

D.these

哪里的排汽门、水门、管道应无因漏汽、漏水而造成的严重结冰，以防压垮房顶？（）

A.汽机房0米层

B.锅炉房底部

C.外围系统

D.厂房建筑物顶