it CAn BE inFErrED thAt thE DElAyED usE oF ExposED iron struCturEs in trADitionAl stylEs oF ArChitECturE is BEst ExplAinED By ______.
A．thE imprACtiCAlity oF using iron For smAll, nonCommErCiAl BuilDings
B．thE AssoCiAtion oF iron ArChitECturE with thE proBlEms oF thE inDustriAl rEvolution
C．thE gEnErAl BEliEF thAt iron oFFErED lEss rEsistAnCE to FirE AnD hArsh wEAthEr thAn trADitionAl mAtEriAls
D．thE gEnErAl pErCEption thAt iron struCturEs wErE not BEAutiFul in AppEArAnCE