CE:as seen作为状语，修饰紧跟的动作，在C里面修饰的是is believed to be，在E里面修饰的是grow，根据语义应该选E

on earth不能放在句首，如果理解成“在地球上”，则应为on the earth

as seen句子的主语应该是trees，划线部分句子是倒装的。

1、among倒装，2、as seen C里修饰句子，E里就近修饰the rate at which trees grow.

谓语动词用is，主语是the rate
as seen基金修饰tree growth，而C选项修饰sunspot cycle错误
on earth位置没有e好

见识了。。谓语不是一个单词的情况下的倒装，主语放在整个is believed to be的后面

就近原则很重要

(A) among倒装，主语应该是the rate，所以应该用单数is。
(B) among倒装，主语应该是the rate，所以应该用单数is；tree应该用复数，使未划线部分的their有 一致的指代对象。
(C) on earth 放置句首修饰整个句子，不符合逻辑；their 的指代存在歧义，离它最近的是 sunspot cycles，未划线部分的 as seen 应该要紧跟其修饰的名词。
(D) tree应该用复数，使未划线部分的their有一致的指代对象；谓语结构不完整，应该用is believed被动语态。
(E) 正确，on Earth修饰indications，主语是the rate，谓语动词用单数is。

some things wrong with c:
* the placement of 'on earth' is just as problematic as in choice a (again, the sentence seems to be saying that residents of other planets disagree with us).

* 'as seen in the rings...' is a modifier that must be placed next to the thing that it modifies, which is 'the rate at which trees grow'. the way choice c is currently written, it says that indications of sunspot cycles can be seen directly in the rings - and it also implies that sunspot cycles (instead of trees) have rings!

A says that tree growth is believed to be a good indicator by people on earth
and finally, yes, 'the rate that' is simply... wrong. things don't 'happen a rate'; they happen at a rate, so that preposition has to stay.

E-The rate at which trees grow, as seen in the rings visible in the cross sections of their trunks,is believed to be among the surest indications of sunspot cycles.

为什么不选C:
as seen的修饰对象。as seen说的是“正如（我们在）树桩上的年轮所看到的那样”。
从语义上应修饰树的成长，把句子还原trees grow at the rate as seen in the rings visible in the cross sections of their trunks. 树木增长的速度，从树桩上年轮的圈上可见一斑。
C选项，使得as seen的修饰对象变成了sunspot cycles，语义完全错误了。

这是介词短语提前了。。。。

1-根据句意，说的是the rate is believed，需要主谓一致，排除AB；
2-D选项非完整句子，严重语法错误，排除D；
3-C和E中，查看和题干中之后的句子链接起来是否正确；as seen是一个状语从句，根据定语从句和状语从句这些修饰成分服从就近修饰原则，到前一个句子去找as seen去修饰的成分；C中as seen修饰主句 the rate is believed；E中as seen 修饰which trees grow；根据句意，E的修饰更合理，因此排除C；
4-选E

老师，我可以排除A，B因为are，可以排除D因为不是一个完整句子，但不明白C错在哪里，谢谢了。

【倒装】百科。
地点范围介词短语前置
表示地点范围的介词包括：among、between、in、at、beneath等等，例如：
(1) The rate at which trees grow is believed to be among the surest indications on Earth of sunspot cycles
(2) Among the surest indications on Earth of sunspot cycles is believed to be the rate at which trees grow
(1)(2)两个例句完全相等。(2)属于倒装结构。

又错一遍：
E: 倒装，还原后为：the rate at which trees grow is believed to be among the Among the surest indications on Earth of sunspot cycles
A：on earth 修饰整个句子不对，主语为the rate，谓语动词需要为单数，the rate that trees grow也怪怪的
BD: 结构一团乱，排除
C：on earth 修饰整个句子不对

1. A是倒装句，应该用“is belived to”
2. 状语修饰最近的句子，C是“is belived to be”, E是"at which tree grow," 再看后面衔接的“as seen in the rings visible in the cross sections of their trunks.” 根据句意，年轮应该是看出树在增长。

seen就近修饰

among引起倒装主语是rate，主谓一致