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。

想问一下老师这题的定位思路是如何的，大后天就考了。答案是C，还想听一下D的话为什么不能选

想问下老师这题的思路。为什么B选项不对，对于比例是没办法说明坏的多还是少，需要一个说人数一样多来补充证明说motorized确实比non m多。为什么要D

想问下老师这题的思路是怎么的，assumption的题目应该怎么做，之前是老师的方法是说把assumption看成是一个argument的补充原因，好像在这里用不上？有点急

想问下老师这题的思路是怎么样的，快考试了有点急

想让老师理一下这篇阅读的文章结构还有解决下第4题

想问问唐塘老师这题思路是什么样的，我做的时候只get到了预算是由税的2%来的，然后一个公司现在由1%的这个城的雇佣员工组成（不知道对不对），还有想问下这题在考试里大概是什么水平的题目

想问下唐塘老师，这题我没看懂题目的意思，查了意思后说是调和xxxx，也不是很明白，然后我看说c讲了两个不同状态的婴儿，对于牛奶的吸收的不同，跟原文里呈现了两种婴儿的比较比较一样，就选了，这思路对么？答案是c

想请问下唐塘老师这题的思路是什么，感觉一点思路都没有

请王文静老师答疑

想问一下may老师，如果这一题把题干改成 a sequence of 6n conseuctive integers, 那是像这样分析吗。