单选题Although the crankshafts of medium diesel engines appear to be robust, they rely on the support of （） to develop their full strength.Athe piston rodsBthe crank throwsCthe thrust bearingsDthe main bearings
单选题
Although the crankshafts of medium diesel engines appear to be robust, they rely on the support of （） to develop their full strength.
A
the piston rods
B
the crank throws
C
the thrust bearings
D
the main bearings
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