单选题（） into the cylinder because no fuel can burn （） it.AAir must be admitted；withoutBOil must be injected；withoutCAir must be admitted；withDOil must be injected；with
单选题
（） into the cylinder because no fuel can burn （） it.
A
Air must be admitted；without
B
Oil must be injected；without
C
Air must be admitted；with
D
Oil must be injected；with
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