prep1-139 还是不懂

139.      (32262-!-item-!-188;#058&006043)

On Earth, among the surest indications of sunspot cycles are believed to be the rate that trees grow, as seen in the rings visible in the cross sections of their trunks.

(A) On Earth, among the surest indications of sunspot cycles are believed to be the rate that trees grow

(B) On Earth, among the surest indications of sunspot cycles are, it is believed, the rate of tree growth

(C) On Earth, the rate at which trees grow is believed to be among the surest indications of sunspot cycles

(D) Among the surest indications on Earth of sunspot cycles, believed to be the tree growth rate

(E) Among the surest indications on Earth of sunspot cycles is believed to be the rate at which trees grow

C怎么不对了？

GMAC更喜欢倒装句，比较牛

后面的as seen应该紧跟修饰名词，修饰的是树的生长，而C中离as seen 最近的是sunspot circle 不如E好

as引导非限制性定语从句，指代整个主句内容，从句可置于句首，句中或句尾。在这里要修饰trees grow，同which,that一样要跟修饰的对象尽量靠近否则会有歧义。as比较特殊的，不是修饰单个名词，而是修饰动作的。

说几个看法，欢迎拍砖。这个their我认为是trees；

我看这个题目的时候，特别关注了一下seen, 应该呼应的是indications.

谢谢提醒，貌似突然懂了这个题~

grow as seen in the rings visible in the cross sections
                    of their trunks.

中的HIGHLIGHT部分是平行对称的吧！as seen作为好像...讲，相当于是比较

所以要平行？！个人意见，仅供参考。还望NN们赐教~~！

赞！