A diesel engine is usually more efficient than a spark ignition engine

1.	A diesel engine is usually more efficient than a spark ignition engine because
A.	Diesel being heavier hydrocarbon, releases more heat per kg than gasoline
B.	The air standard efficiency of diesel cycle is higher than the Otto cycle, at a fixed compression ratio
C.	The compression ratio of a diesel engine is higher than that of an SI engine
D.	Self-ignition temperature of diesel is higher than that of gasoline
Answer» D. Self-ignition temperature of diesel is higher than that of gasoline

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A diesel engine is usually more efficient than a spark ignition engine because

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