一只空瓶质量为0.1kg，装满水后总质量为0.6kg，该瓶的容积为多少m³．

With the crop’s production _____ rapidly, food price is _____ year by year.　　

A．go up; going down　　　　　

B．going up; go down　　

C．going down; going up　　　　

D．going down; go up