[求助]大全987-140句子的逻辑连接与因果关系

140.        As the housing affordability gap widens, middle-income families are especially hard-hit, and these families can no longer qualify to buy homes, and rising rental rates force them to use far more than the standard 25 percent of their incomes for housing, leaving them with no equity or tax write-offs to offset the expenditures.

(A) and these families can no longer qualify to buy homes, and

(B) since these families can no longer afford to buy homes, furthermore

(C) for these families can no longer afford to buy homes, yet

(D) and these families can no longer afford to buy homes; however,（C）

(E) and these families can no longer afford to buy homes, for

大全的注解上面给出的答案是C,但是我认为E才是正确的答案。问题的焦点就在于怎么理解 "rising rental rates force them to use far more than the standard 25 percent of their incomes for housing" 这句话和"these families can no longer afford to buy homes" 之间的逻辑关系， 我个人认为，这里有明显因果关系，因为rising rental 迫使他们花费更多的收入for housing 所以 他们才供不起房.

期待大家一起来讨论