单选题The two-stroke cycle begins with the piston coming up from the bottom of its stroke, with scavenge ports in the sides of the cylinder being ().AshutBclosingCopenedDclosed

单选题
The two-stroke cycle begins with the piston coming up from the bottom of its stroke, with scavenge ports in the sides of the cylinder being ().
A

shut

B

closing

C

opened

D

closed


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