单选题One major disadvantage of a low-speed diesel as compared to a steam main-propulsion system is（）.Athe extra weight required for the diesel reduction gearingBa minimum speed for the engines that limits the minimum speed of the vesselCthe higher fuel consumption per SHPDthe low efficiency of the system when a controllable pitch propeller is used
单选题
One major disadvantage of a low-speed diesel as compared to a steam main-propulsion system is（）.
A
the extra weight required for the diesel reduction gearing
B
a minimum speed for the engines that limits the minimum speed of the vessel
C
the higher fuel consumption per SHP
D
the low efficiency of the system when a controllable pitch propeller is used
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