[求助]GWD4-38 (搜索过，没有找到满意答案)

Two centuries ago, Tufe
                Peninsula became separated form the mainland, isolating on the newly formed Tufe
                    Island a population of Turfil sunflowers.  This population’s descendants grow to be, on average, 40 centimeters shorter than Turfil sunflowers found on the mainland.  Tufe
                Island is significantly drier than Tufe
                    Peninsula was.  So the current average height of Tufe’s Turfil sunflowers is undoubtedly at least partially attributable to changes in Tufe’s environmental conditions.

Which of the following is an assumption on which the argument depends?     C

1. There are no types of vegetation on Tufe
                           Island that are known to benefit from dry conditions.
2. There were about as many Turfil sunflowers on Tufe
                       Peninsula two centuries ago as there are on Tufe
                           Island today.
3. The mainland’s environment has not changed in ways that have resulted in Turfil sunflowers on the mainland growing to be 40 centimeters taller than they did two centuries ago.
4. The soil on Tufe
                           Island, unlike that on the mainland, lacks important nutrients that help Turfil sunflowers survive and grow tall in a dry environment.
5. The 40-centimeter height difference between the Turfil sunflowers on Tufe
                           Island and those on the mainland is the only difference between the two populations.

C 取非后

The mainland’s environment has changed in ways that have resulted in Turfil sunflowers on the mainland growing to be 40 centimeters taller than they did two centuries ago.

说明依然是环境的变化引起的heigh的改变啊

文中的结论the current average height of Tufe’s Turfil sunflowers is undoubtedly at least partially attributable to changes in Tufe’s environmental conditions. 没有被削弱阿？

PS: Tufe’s Turfil  应该只的是 Tufe Peninsula 's Turfil sunflowers and Tufe Island's Turfil sunflowers 吧 

The mainland’s environment has changed in ways that have resulted in Turfil sunflowers on the mainland growing to be 40 centimeters taller than they did two centuries ago.

说明依然是环境的变化引起的heigh的改变啊

文中的结论the current average height of Tufe’s Turfil sunflowers is undoubtedly at least partially attributable to changes in Tufe’s environmental conditions. 没有被削弱阿？

PS: Tufe’s Turfil  应该只的是 Tufe Peninsula 's Turfil sunflowers and Tufe Island's Turfil sunflowers 吧 

C 取非后

The mainland’s environment has changed in ways that have resulted in Turfil sunflowers on the mainland growing to be 40 centimeters taller than they did two centuries ago.

说明依然是环境的变化引起的heigh的改变啊

文中的结论the current average height of Tufe’s Turfil sunflowers is undoubtedly at least partially attributable to changes in Tufe’s environmental conditions. 没有被削弱阿？

PS: Tufe’s Turfil  应该只的是 Tufe Peninsula 's Turfil sunflowers and Tufe Island's Turfil sunflowers 吧
 

你把C取非后,是weaken了.C取非后就说的是:mainland上的flower比岛上的高40cm是mainland的env发生变化了.

这就weaken文章的结论(是说岛上的矮40am是因为从mainland到岛上的env变化了引起的)了.

谢谢 wycg

使我搞错了，题目理解上的问题。

题目的意思是 从半岛变成小岛后的环境变化，排除大陆的环境变化的他因

以下是引用nearmiss在2006-9-3 13:24:00的发言：
为什么E不对，E排除了其它的不同性，说明可能不是岛上环境引起的。

"E排除了其它的不同性" 不能推出来"说明可能不是岛上环境引起的".的呀.