Which of the following statements concerning the lubrication of diesel propulsion engines used in vessels over 300 gross tons is most accurate?（）
A. Lubrication systems using engine driven lube oil pumps do not require any additional independent arrangement when such arrangements have been proven reliable
B. The use of engine driven pre-lube pumps is permitted on vessels with propulsion systems developing less than 500 shaft horsepower
C. When forced lubrication is used for propulsion engines, one independently driven stand-by pumps is to be provided in addition to the necessary pumps for normal operation
D. Lubrication systems where two oil coolers are fitted require a minimum of two temperature control devices which may be actuated by similar sensor
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