单选题Oil control rings used in two-stroke/cycle diesel engines are located near the bottom of the piston skirt in order to （）Aincrease the liner area covered by the oil filmBmaintain an oil film on the lower liner where scuffing is prevalentCkeep excess oil away from intake and exhaust portsDhelp cushion piston skirt side thrust by providing a hydrodynamic oil wedge
单选题
Oil control rings used in two-stroke/cycle diesel engines are located near the bottom of the piston skirt in order to （）
A
increase the liner area covered by the oil film
B
maintain an oil film on the lower liner where scuffing is prevalent
C
keep excess oil away from intake and exhaust ports
D
help cushion piston skirt side thrust by providing a hydrodynamic oil wedge
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