During the power stroke of a four-stroke/cycle diesel engine, most of the side thrust of a trunk-type piston is absorbed by the（）

A.cylinder pressure
B.flame intensity
C.exhaust gas temperature
D.crankshaft axial alignment

A.decreased compression pressure
B.increased lube oil pressure
C.lower lube oil temperature
D.excessive leakage past the piston rings

A.dwell-tachometer
B.exhaust gas pyrometer
C.fuel flow rate mete
D.exhaust gas analyzer