According to a theory advanced by researcher Paul Martin，the wave of species extinctions that occurred in North America about 11,000 years ago，at the end of the Pleistocene era，can be directly attributed to the arrival of humans，i.e.，the Paleoindians， who were ancestors of modern Native Americans. However，anthropologist Shepard Krech points out that large animal species vanished even in areas where there is no evidence to demonstrate that Paleoindians hunted them.Nor were extinctions confined to large animals： small animals，plants，and insects disappeared，presumably not all through human consumption. Krech also contradicts Martin's exclusion of climatic change as an explanation by asserting that widespread climatic change did indeed occur at the end of the Pleistocene. Still，Krech attributes secondary if not primary responsibility for the extinctions to the Paleoindians，arguing that humans have produced local extinctions elsewhere.But，according to historian Richard White，even the attribution of secondary responsibility may not be supported by the evidence. White observes that Martin's thesis depends on coinciding dates for the arrival of humans and the decline of large animal species，and Krech，though aware that the dates are controversial，does not challenge them；yet recent archaeological discoveries are providing evidence that the date of human arrival was much earlier than 11,000 years ago. 　3. In the last sentence of the passage， the author refers to “recent archaeological discoveries” (lines 27-30) most probably in order to 　　(A) Refute White's suggestion that neither Martin nor Krech adequately account for Paleoindians' contributions to the Pleistocene extinctions 　　(B) Cast doubt on the possibility that a more definitive theory regarding the causes of the Pleistocene extinctions may be forthcoming 　　(C) Suggest that Martin's， Krech's， and White's theories regarding the Pleistocene extinctions are all open to question 　　(D) Call attention to the most controversial aspect of all the current theories regarding the Pleistocene extinctions 　　(E) Provide support for White's questioning of both Martin's and Krech's positions regarding the role of Paleoindians in the Pleistocene extinctions 老师，我在做这道题的时候，首先定位到最后一句觉得没说什么重点，就有个yet转折，可能这是用来驳斥前面的某些观点的。所以看选项找有没有驳斥的意思的， 发现5个选项全都在驳斥。。。心里慌了往前找。再回去找的时候时间已到。我就随便选了个B（时间一到各种混乱），因为在做这篇文章之前，我大体看了下原文，记住了原文讲的是P反驳M，W反驳P。后来答案我也看明白了，我认为我做这道题的思路出现了偏差，我想问一下应该怎么修正。

想问下为什么选D 中间没有连接词感觉好怪

请教小梅老师 这个题目 我算的90 为什么不对呢 102这个按照正常列公式该咋列呢？ 谢谢老师

小梅老师请问这道题的几种变体怎么区分呢？ 1）no boy stands btw girls是指BBB和GGG必须在一块是嘛？ GBBG这种也是不允许的嘛？ 2）它和no boy stands btw 2 girls有什么区别嘛？ 3）三男三女排一行 两两隔开又和前面有什么区别

请教39题 谢谢小梅老师

老师 请教一下39和40题 39应该怎么做呢？有点没思路 40是选择E吗老师 谢谢老师！

请问一下唐瑭老师，老师上逻辑课举的试验田的例子，C选项：两块试验田的形状不同，这个是无关的，如果改成：两块试验田的形状不同，但形状也会影响产量，那这个是有关还是无关呢？为什么呢？

请唐塘老师分析一下这道题，我感觉题目中问的是杂志新政策和intended effect之间的关系，我感觉五个选项都无关，老师可以分析一下五个选项吗？谢谢

请唐塘老师分析一下这道题，谢谢，看不懂最后一句话的内容，不知道文章最后一句话的重心是什么

请唐塘老师分析一下这道题，谢谢

这道题C感觉是对的因为可以降低运输成本增加收益