In order to reduce the increasing prices of vegetables , the toll(过路费)           if a truck carrying them passes through a toll station .

A．cancels

B．is cancelled

C．was cancelled

D．had been cancelled

采用试锥法测定水泥净浆标准稠度时，当测得的试锥贯入深度是31mm，第二次应加的水量应调整为138ml。（）