why wAs thE unitED stAtEs CAllED A "mElting pot"
A．most immigrAnts hAvE sEttlED in Big CitiEs.
B．its populAtion Consists oF pEoplE From vArious CountriEs.
C．most pEoplE tEnD to ForgEt whErE thEir AnCEstors CAmE From.
D．pEoplE gAthErED in rACiAl groups.