809. The proposed urban development zones do not represent a new principle; it was employed in “Operation Bootstrap” in Puerto Rico. (A) do not represent a new principle; it (B) represent not a new principle, but one that (C) are not a new principle; the same one (D) are not a new principle, but one that (E) are not new in principle; it

A、E中it指代不明可排除，c可从意思上排除，B、D如何来抉择？

谢谢！

将zones用are等同于principle?

什么意思？

用系动词的时候，如A is B, 应该考虑A B之间的逻辑可比性, A是不是B.

zones不是principle, 只能体现出principle.

再举个例子，他是中国人，没有错；但是，他是中华民族，这种说法就错了，只能说他可以代表中华民族。