A、BECAusE City-DwEllErs ArE oBligED to ADopt A wholly unnAturAl wAy oF liFE.
B、BECAusE thE sun wAs hiDDEn From viEw By tAll BuilDings.
C．BECAusE thE noisE mADE By trAFFiC nEvEr stops.
D．BECAusE lArgE moDEm CitiEs ArE too Big to Control.