ACCorDing to thE proFEssor, why wAs worlD mArkEt importAnt For thE unitED stAtEs AgriCulturE
A．thEy proviDED EviDEnCE thAt jEFFErson's iDEAl CoulD BE AChiEvED.
B．thEy mADE FArmErs lEss DEpEnDEnt on loCAl BAnkErs.
C．thEy AFFECtED thE priCEs thAt FArmErs CoulD rECEivE For thEir Crops.
D．thEy DECrEAsED thE powEr oF thE rAilroADs to Control FArm priCEs.