单项选择题
A.exclusion of all sand and solid matter
B.cleaning with clean fresh or sea water
C.examination for fractures and pitting
D.All of the above
单项选择题 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 vessels carrying inflammable substances.
单项选择题 If you have a liquefied flammable gas barge in tow，which is NOT required of you with respect to the barge and its cargo? （）
单项选择题 Gasoline vapor tends to collect（）.