thE Author CitEs mr. smith's survEy in orDEr to show thAt ______.
A．most immigrAnts ArE EithEr highly skillED or poorly unskillED
B．immigrAnts ArE mostly thosE who rECEivED littlE EDuCAtion BEForE ArrivAl
C．immigrAnts tAkE up A lArgEr proportion oF AmEriCAn populAtion thAn thC nAtivEs
D．thErE ArE morE highly skillED immigrAnts in AmEriCA thAn unskillED immigrAnts