Gwd-2-28, 请教,多谢!

hhnelson

: Which of the following most logically completes the argument?

A certain cultivated herb is one of a group of closely related plants that thrive in soil with high concentrations of metals that are toxic to most other plants. Agronomists studying the herb have discovered that it produces large amounts of histidine, an amino acid that, in test-tube solutions, renders these metals chemically inert. Possibly, therefore, the herb’s high histidine production is what allows it to grow in metal-rich soils, a hypothesis that would gain support if ______.

A: histidine is found in all parts of the plant – roots, stem, leaves, and flowers

B: the herb’s high level of histidine production is found to be associated with an unusually low level of production of other amino acids

C: others of the closely related group of plants are also found to produce histidine in large quantities

D: cultivation of the herb in soil with high concentrations of the metals will, over an extended period, make the soil suitable for plants to which the metals are toxic

E: the concentration of histidine in the growing herb declines as the plant approaches maturity

我选C, 答案是D.为什么?

lawyer_1

同意C。D的土壤是否适应该HERB和假设无关。

flymind

同意D. 因为" it produces large amounts of histidine, an amino acid that, in test-tube solutions, renders these metals chemically inert.", 所以土壤适合其他植物生长. 而C为无关, 即使成立, 还需要进一步论证是否能不能renders these metals chemically inert.

msfox

同意C，题中的“a hypothesis 是allows it to grow in metal-rich soils”，与D中的其他植物无关。

三脚猫

实在看晕了，ＮＮ快来啊

yrhan

我同意选D,我觉得重点在于第一句话的理解A certain cultivated herb is one of a group of closely related plants that thrive in soil with high concentrations of metals that are toxic to most other plants,应该是这A certain cultivated herb 是唯一一个不受metals影响的,而且other plans in the  group of closely related plants 是受影响的,之所以这个Group都可以thrive,那应该是D答案

flyfly

同意D ,因为herb 是的有毒的金属惰性，所以其他东东可以生长

windweed

我选C, 因为去解释现象的hypothesis为: the herb’s high histidine production is what allows it to grow in metal-rich soils. 证据是histidine renders these toxic metals chemically inert.所以argument 说histidian production 是使A certain cultivated herb of one of a group of closely related plants 能够grow的原因.

C 说明了, 这个hypothesis没有以偏盖全. 如果别的closely related plants也是因为这个原因而growth in toxic soil. 这个hypothesis因此得到support.

D 我认为是无关选项, 尤其说到over an exdended period, 原文没有说histidine 只能暂时让plants survive.

忘进一步讨论

icekun

xdf绿皮书p65，178题答案e

tuzq

支持D，虽然不是很完美。－一种解释可以是D说明Herb并不是自身对金属有免疫力，而是对土壤有所改变。

C觉得是无关的。