单选题 What the passage tells us can be summarized by the statement ______.

A、 potential disorganization is present in the American family
B、 social development results iii a decline in the importance of traditional families
C、 the movement of a family is one of the factors in raising its social status
D、 family disorganization is more or less the result of mobility

【正确答案】 D

【答案解析】文章主要在讲述三种mobility：movement in space，movement up or down in social status，and the movement of ideas对家庭关系的影响，选项D正确。