[求助]CR

Ronald: According to my analysis of the national economy, housing prices should not increase during the next six months unless interest rates drop significantly.

Mark: I disagree. One year ago, when interest rates last fell significantly, housing prices did not increase at all.

It can be inferred from the conversation above that Mark has interpreted Ronald’s statement to mean that

(A) housing prices will rise only if interest rates fall

(B) if interest rates fall, housing prices must rise  

(C) interest rates and housing prices tend to rise and fall together

(D) interest rates are the only significant economic factor affecting housing prices（B）

(E) interest rates are likely to fall significantly in the next six months

        The U.S. census is not perfect: thousands of Americans probably go uncounted. However, the basic statistical portrait of the nation painted by the census is accurate. Certainly some of the poor go uncounted, particularly the homeless; but some of the rich go uncounted as well, because they are often abroad or traveling between one residence and another.

Which of the following is an assumption on which the argument above depends?

(A) Both the rich and the poor have personal and economic reasons to avoid being counted by the census.

(B) All Americans may reasonably be classified as either poor or rich.

(C) The percentage of poor Americans uncounted by the census is close to the percentage of rich Americans uncounted.

(D) The number of homeless Americans is approximately equal to the number of rich Americans.（C）

(E) The primary purpose of the census is to analyze the economic status of the American population.