单选题An excessive amount of water is prevented from entering a vessel using a water lubricated stern tube bearing by the use of the （）.Apropeller hubBlignum vitaeCshaft packingDlabyrinth seal
单选题
An excessive amount of water is prevented from entering a vessel using a water lubricated stern tube bearing by the use of the （）.
A
propeller hub
B
lignum vitae
C
shaft packing
D
labyrinth seal
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