单选题The starting air entering the cylinder begins when the piston（）Ahas nearly come to the TDCBhas just past the TDCChas nearly come to the BDCDhas just past the BDC
单选题
The starting air entering the cylinder begins when the piston（）
A
has nearly come to the TDC
B
has just past the TDC
C
has nearly come to the BDC
D
has just past the BDC
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