When one cylinder has a lower compression pressure and higher exhaust gas temperature than any of the other engine cylinders, which of the conditions listed will indicated?（）

A.a cylinder air charge of higher pressure
B.increased pumping losses
C.less valve overlap
D.reduced blow-by

A.low exhaust temperature
B.low firing pressure
C.fuel knock in each cylinder
D.mechanical knock in each cylinder

A.the pump supply pressure
B.the slope of the fuel cam
C.how the plunger is rotated
D.the number of sleeve segments engaged with the rack