A、BECAusE All thE trAsh CAns ArE thE sAmE Color.
B、BECAusE not Enough pEoplE voluntEEr to CollECt thE trAsh.
C．BECAusE most pEoplE Don’t likE to sort thEir trAsh.
D．BECAusE CollECtions ArE not mADE on A rEgulAr BAsis.