单选题（）diesel engines generally have two systems of lubrication:（）a total loss system feeding and a circulating system lubricating the running gear and cooling the pistons.ALarge crosshead type；crossheadsBHigh speed；the cylindersCLarge crosshead type；the cylindersDFour-stroke；pistons and cylinders
单选题
（）diesel engines generally have two systems of lubrication:（）a total loss system feeding and a circulating system lubricating the running gear and cooling the pistons.
A
Large crosshead type；crossheads
B
High speed；the cylinders
C
Large crosshead type；the cylinders
D
Four-stroke；pistons and cylinders
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