At thE EquiliBrium priCE For A proDuCt, thE ______
A、Firms in thE mArkEt ArE mAximizing thEir totAl rEvEnuE.
B．ConsumErs in thE mArkEt hAvE spEnt All oF thEir inComE.
C．Firms in thE mArkEt ArE mAximizing thEir totAl output.
D．Firms in thE mArkEt ArE just BrEAking EvEn.
E．quAntity DEmAnDED By ConsumErs EquAls thE quAntity suppliED By Firms.