美国的linking arrangement和他国的是同一个事物吗？难道不应该是类似事物，即应该是those不是they？

如果指代linking arrangements，难道不应该是it而不是they吗？

they同物指代！！
in美国究竟应该修饰名词还是修饰动词可以看，比较的是名词还是动词，比较的是有没有evolved

those/that同类不同体，they/it同体。
句子的意思是比较United States的arrangements和most other developed countries的arrangements，所以不能将in the United States直接放在Linking arrangements的后面，否则后面的they就代替的是United States的arrangements. 排除BD。
A不能用among，后面的they have时态错误。
剩下CE，C语义错误，变成了United States和most other developed countries都没有evolve。

补全句子应该是Linking arrangements between secondary schools and the workplace never evolved in the United States as Linking arrangements between secondary schools and the workplace evolved in most other developed countries.
C. 前面的主句部分直接copy过来就成了“Linking arrangements between secondary schools and the workplace never evolved in the most other developed countries”。其字面意思为“学校和工作的联系在其他发达国家也从未发展”，错误
E. they 代指 Linking arrangements between secondary schools and the workplace，did 代指 evolved，正确

C选项：as身后直接为“in the most other developed countries”这一状语，说明省略了主句部分，但前面的主句部分直接copy过来就成了“Linking arrangements between secondary schools and the workplace never evolved in the most other developed countries”。其字面意思为“学校和工作的联系在其他发达国家也从未发展”。但合理的意思应该是在美国没发展，但在别的国家发展了。

as身后直接为“in the most other developed countries”这一状语，说明省略了主句部分，但前面的主句部分直接copy过来就成了“Linking arrangements between secondary schools and the workplace never evolved in the most other developed countries”。其字面意思为“学校和工作的联系在其他发达国家也从未发展”。但合理的意思应该是在美国没发展，但在别的国家发展了。

即便c选项在语法上无错误，但扭曲的原句语义

注意选项 C between secondary schools and the workplace never evolved in the United States as
C比对的是in the United States和in most other developed countries
而E as they did，比对的是evolve与否这个动作本身。

MGMAT says that as can also appear with a phrase, rather than a full clause when as clause acts as a modifier.
However, there is no comma in C and thus “as in most other developed countries” has to be read not as a modifier but as a part of comparison as trying to convey. But for proper comparison we need a verb and E gives us that lacking “they did”, avoiding the mistake made by C. Therefore, C is incorrect not for ambiguity but for wrong structure.

as is differently used than as__ as__ and more/less__ than__. While using as__ as__ and more/less__ than__ you can omit units, verbs, and even whole clauses from the second term if there is no ambiguity,
Linking arrangements... evolved as fast in the United States as (they did) in most other developed countries.

https://gmatclub.com/forum/linking-arrangements-among-secondary-schools-and-the-workplace-never-294390.html

体会CE语义的差异

C选项：as身后直接为“in the most other developed countries”这一状语，说明省略了主句部分，但前面的主句部分直接copy过来就成了“Linking arrangements between secondary schools and the workplace never evolved in the most other developed countries”。其字面意思为“学校和工作的联系在其他发达国家也从未发展”。但合理的意思应该是在美国没发展，但在别的国家发展了。

A：as身后是“they have”，为“they have done sth”的省略，但as前面并没有完成时，即“have”出现，所以，as 后面出现完成时形式的省略是错误的。

B：in the United States放在arrangements之后，作定语，意为“在美国的、中学和工作间的 联系”；as之后的they也就指代了“在美国的联系”。但我们不能说“在美国的联系在别的国家发展”，应该是说“联系在美国发展 vs 联系在别的国家发展”，即做evolved的状语才合理。

E选项：正确。they did为“they evolved”的省略，they指代“linking arrangements between secondary schools and the workplace ”。后者“they指代“linking arrangements between secondary schools and the workplace ”。”是怎么指代的？？they 指代arragements对吧

这里是将schools和workplace看成两个整体，在学校和工作地之间的联络安排，用between/and；如果指的是各学校之间的联络安排或者（2个以上）工作地之间的联络安排，则是三者及以上，用among

C、D项区别

One might get the feeling that C and E mean the same thing. It is not so in that C has a subtle but substantial error of intent. C says that the listing arrangements never evolved in the US just as in the same way the arrangements did not evolve in most other developed countries. In other words, it tends to mean that in other countries also they did not evolve. This is a grave flaw. The original intent is that while in other countries the arrangements evolved smoothly, in the US, they did not.

C选项：as身后直接为“in the most other developed countries”这一状语，说明省略了主句部分，但前面的主句部分直接copy过来就成了“Linking arrangements between secondary schools and the workplace never evolved in the most other developed countries”。其字面意思为“学校和工作的联系在其他发达国家也从未发展”。但合理的意思应该是在美国没发展，但在别的国家发展了。

among指三者以上，between指两者之间
between……and……
linking arrangement never evolved in US as （they evolved） in other countries 明白比较内容和比较对象，选项C只比较了国家，没有比较他们有没有evolve

主语和谓语动词能否省略，只保留时间/范围状语等，取决于将前句的谓语动词+谓语动词的时态/语态/肯定否定式平移过来后，被省略句的逻辑是否合理。特殊情况：如果前后都有时间状语，比较不同的时间下的情况，可以省略主谓只保留时间状语，不管时态是否一致。