单选题An electric heater built into some smaller diesel engines is used to （）.Araise lube oil viscosity for easier starting in cold weatherBincrease air inlet temperatureCincrease compression ratioDincrease jacket water temperature for easier starting in cold weather
单选题
An electric heater built into some smaller diesel engines is used to （）.
A
raise lube oil viscosity for easier starting in cold weather
B
increase air inlet temperature
C
increase compression ratio
D
increase jacket water temperature for easier starting in cold weather
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