GRE 陈虎平阅读36一套逻辑单题 求解！！

deeeemi

总是做不对所谓最简单的逻辑单题是什么鬼好想哭。各位大神救救我！！

题目是第11套的第13题：
Scientists have sought evidence of long-term solar periodicities by examining indirect climatological data, such as fossil records of the thickness of ancient tree rings. These studies, however, failed to link unequivocally terrestrial climate and the solar-activity cycle, or even to confirm the cycle's past existence.


It can be inferred from the passage that studies attempting to use tree-ring thickness to locate possible links between solar periodicity and terrestrial climate are based on which of the following assumptions?

• AThe solar-activity cycle existed in its present form during the time period in which the tree rings grew.
• BThe biological mechanisms causing tree growth are unaffected by short-term weather pat terns.
• CAverage tree-ring thickness varies from species to species.
• DTree-ring thicknesses reflect changes in terrestrial climate.
• EBoth terrestrial climate and the solar-activity cycle randomly affect tree-ring thickness.
  

正确答案：D

提问：原文再说，科学家用年轮的厚度（这一气候数据）来为长期的太阳周期性找证据，但是这些研究并没有将陆地气候、太阳周期联系起来。 既然都说了没有将联系建立起来，为什么答案选 D？ 如果选D，不是说两句话前后矛盾：一个假设了认识到年轮和气候、太阳和年轮的联系，一个说没有认识到太阳和气候的联系？

最菜留学狗

assumption题型，如果假设取反，则结论不成立。如果thickness无法反应climate，那么文中fail to link又从何说起？