单选题In a four-stroke cycle diesel engine the intake valves open （）Abefore TDC and close after BDCBafter TDC and close after BDCCbefore TDC and close before BDCDafter TDC and close before BDC
单选题
In a four-stroke cycle diesel engine the intake valves open （）
A
before TDC and close after BDC
B
after TDC and close after BDC
C
before TDC and close before BDC
D
after TDC and close before BDC
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