A、BECAusE thErE ArE FEwEr pAssEngErs tAking BusEs.
B、BECAusE City trAnsport hAs BEEn FinAnCiAlly in DiFFiCulty.
C．BECAusE thEy tAkE up A lot oF roAD spACE.
D．BECAusE thEy hAvE pollutED thE City Air.