Los Angeles has a higher number of family dwellings per capita than any large city. A) a higher number of family dwellings per capita than any large city B) higher numbers of familiy dwellings per capita than any other large city C) a higher number of family dwellings per capita than does any other large city D) higher numbers of family dwellings per capita than do other large cities E) a high per capita number of family dwellings more than does any other large city 快考试了，比较省略还有问题，请教大家，答案是B，我选C B/C如何抉择，does究竟什么时候可以省略，什么时候不能省......拜谢。 | 
