thE u.s. hAs to DEAl with thE proBlEms Arising From vEhiClE usE hE CAusE______.
A．most AmEriCAns ArE rEluCtAnt to switCh to puBliC trAnsportAtion systEms
B．thE prEsEnt lEvEl oF oil priCEs is ConsiDErED unACCEptABlE
C．othEr CountriEs will protEst its inCrEAsing grEEnhousE Emissions
D．it shoulD tAkE A lEAD in ConsErving nAturAl rEsourCEs