Which One of the Following Determines the Material Price Variance

Which one of the following determines the material price variance?

A) The difference between actual price per unit and standard price per unit times the quantity of material purchased from suppliers
B) The difference between actual price per unit and standard price per unit times standard quantity of material used for the achieved level of production
C) The difference between actual quantity of material purchased and the actual quantity of material used times the standard price of material per unit
D) The difference between actual quantity of material purchased and the actual quantity of material used times the actual price of material per unit purchased