Q5 to Q7:

According to a theory advanced

by researcher Paul Martin, the wave

of species extinctions that occurred

Line in North America about 11,000 years

(5) 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

(10) Shepard Krech points out that large

animal species vanished even in areas

where there is no evidence to demon-

strate that Paleoindians hunted them.

Nor were extinctions confined to large

(15) 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

(20) 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,

(25) arguing that humans have produced

local extinctions elsewhere. But,

according to historian Richard White,

even the attribution of secondary

responsibility may not be supported

(30) 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

(35) 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.

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Which of the following, if true, would most weaken Krech’s objections to Martin’s theory?

1. Further studies showing that the climatic change that occurred at the end of the Pleistocene era was even more severe and widespread than was previously believed
2. New discoveries indicating that Paleoindians made use of the small animals, plants, and insects that became extinct
3. Additional evidence indicating that widespread climatic change occurred not only at the end of the Pleistocene era but also in previous and subsequent eras
4. Researchers’ discoveries that many more species became extinct in North America at the end of the Pleistocene era than was previously believed
5. New discoveries establishing that both the arrival of humans in North America and the wave of Pleistocene extinctions took place much earlier than 11,000 years

答案B， 我选C 请NN指教

我也选了C

这么想的：K反对M之处在于K认为1：天气是一个影响因素,因为climatic change did indeed occur at the end of the Pleistocene. 。2：hunting至少不是首要原因，因为“large animal species vanished even in areas where there is no evidence to demonstrate that Paleoindians hunted them”

c说climatic change occurred not only at the end of the Pleistocene era but also in previous and subsequent eras，是一个有因无果的削弱（在承认原文开头所说的extinction发生在the end of the Pleistocene era 的前提下）

B说的Nor were extinctions confined to large animals: small animals, plants, and insects disappeared, presumably not all through human consumption。没看懂意思，请问这句话是谁的立场？我觉得是K的。

请大家帮我看看我的错在哪里，B对在哪里？

谢谢！