单项选择题
The spatial distribution of different racial and ethnic populations demonstrates that segregation persists in virtually all of America’s housing markets, from large urban areas to rural counties. What exactly are the ill-Line effects of this demographic isolation The most extreme geographic segregation is unique to black Americans and apparently unrelated to economic status and not explained by preferences for the residence, thus strongly suggesting the persistence of racial discrimination. In contrast to poor whites, who typically live dispersed among better-off families, poor blacks, because of residential segregation, are concentrated in poor neighborhoods. As a result, residential segregation contributes to the problems of these areas, including high concentrations of poverty, educational failure, unemployment, extramarital parenthood, crime, and high mortality. In addition, the increasing importance of suburbs as centers for commerce and habitation has drained resources frominner cities and led to a cyclic decline in the political will to address poverty and urban decline, both of which disproportionately affect ethnic minorities.
According to the passage, all of the following factors have been associated as either a cause or effect of the emergence of segregated black neighborhoods EXCEPT（）. A．The failure of the educational system to help improve blacks’’ economic status
B．Political apathy on the of the authorities to solve the problem of segregation
C．A preference on the part of blacks concerning where they choose to live
D．Rising rate of unemployment among the black community
E．Racial conflict between the black community and other communities