List three causes of a favorable direct materials price variance. (Select three possible answers.) A. Budgeted purchase prices were set without careful analysis of the market. B. The purchasing manager bought in smaller lot sizes than budgeted, thus not obtaining the purchase discounts that were factored in the budget. C. Materials prices increased unexpectedy due to industry shortage. D. Materials prices decreased unexpectedly due to industry oversupply. E. The materials purchasing officer negotiated more skilfully than was planned in the budget