单选题The main purpose of an electric space heater installed in a large AC generator is to （）Aprevent the windings from becoming brittleBprevent moisture from condensing in the windings during shutdownCprevent acidic pitting of the slip ringsDkeep the lube oil warm for quick starting
单选题
The main purpose of an electric space heater installed in a large AC generator is to （）
A
prevent the windings from becoming brittle
B
prevent moisture from condensing in the windings during shutdown
C
prevent acidic pitting of the slip rings
D
keep the lube oil warm for quick starting
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