单项选择题
A spanner is a（）.
A.cross connection line between two main fire lines B.special wrench for the couplings in a fire hose line C.tackle rigged to support a fire hose D.none of the above
单项选择题 A long splice in a line（）.
单项选择题 A hook that will release quickly is a（）.
单项选择题 （）should not be considered as components as fire installations.
