关于代词指代的问题 想请教一下

dkswoah

Critical-thinking instruction is predicted on two assumptions: that there are clearly identifiable thinking skills that students can be taught to recognize and apply appropriately, and if recognized and applied, students will become more effective thinkers.

A   if recognized and applied, students
B   if these skills are recognized and applied, that students
C   if students recognize and apply them, that they
D   that if recognized and applied, students
E    that if students recognize and apply these skills, they
正确答案E
做题方法
句子说的两个 assumption     并列that不省略   ABC 都排除2
D if  recognized  。。。。这里省略有问题。。。   应该是 skills were recognized。。。  可是文章当成了 students was recognized   严重错误
看E    之前做过很多  代词指代    超级头疼     有人说一般 代词放在最后面 都容易导致 指代有歧义啊  什么的       好多 我都已经明白  那个代词指的是什么了 可是解析还是说他指代不清了排除了 他
同样这道题  they 很明显是在这里说students的哇      可是那他有没有指代these skills 的可能性呢？
首先前面 有两个复数名词做了 主语和谓语      
我看很多人把代词指代的错误 偏向解释为简洁  比如不用代词 比用代词好    方便理解什么的？  那么这道题呢？
请NN 给我讲讲  关于代词指代的问题吧