关于instead of 是否错误答案的标志问题

Most of Portugal's 250,000 university students boycotted classes in a one-day strike to protest a law that requires them to contribute $330 a year toward the cost of higher education, previously paying $7 per year.

(A) year toward the cost of higher education, previously paying $7 per year

(B) year toward the cost of higher education, for which was previously paid $7 per year

(C) year, compared to the previously $7 per year, toward the cost of higher education

(D) year toward the cost of higher education, instead of the $7 per year required previously for the cost of higher education

(E) year as opposed to the $7 per year required previously for the cost of higher education

正确答案是D, 请分析一下其他几个选项为什么错呢??

还有D选项的instead of 是不是有点问题呢??

Resarch during the past several decades on the nature of laguage and the processed that produce and make it understandable has revealed great complexity instead of underlying-simplicity.

(A) that produce and make it understandable has revealed great complexity instead of underlying simplicity

(B)of producing and understanding it have revealed not underlying simplicity but great complexity

(C) by which it is produced and understood has revealed not underlying simplicity but great complexity

(D) by which it is produced and understood have revealed great complexity rather than underlying simplicity

(E) by which one produces and understands it have revealed great complexity instead of underlying simplicity

答案是A, 又是instead of.

为什么不能选C呢??不是说not..but是优选结构么??

instead of 和rather than共存的时候，杀instead of

第二题中，你只看not...but这样的小东西来开杀是不行的, which指代不正确，马上就能杀

而且你要看逻辑意思，人家写instead of underlying-simplicity.而不是but great complexity underlying-simplicity，不是在用complexity修饰后面。最重要的是人家A选项用了that来指代前面的整个事情是ETS的惯用考法

要从逻辑意思和大方向上先排除不对的选项，而不是看小点，除非杀到两个选项开比的时候，在看类似于instead of这样的东东

太感谢mm了,阿方便留个联系方式?