The use of activity$-$based costing $($ABC$)$ normally results in

A$.$ Equalizing setup costs for all product lines.

B$.$ Substantially greater unit costs for low$-$volume products than is reported by traditional product costing.

C$.$ Substantially lower unit costs for low$-$volume products than is reported by traditional product costing.

D$.$ Decreased setup costs being charged to low$-$volume products.