Plantings of cotton bioengineered to produce its own insecticide against bollworms, a major cause of crop failure, sustained little bollworm damage until this year. This year the plantings are being seriously damaged by bollworms. Bollworms, however, are not necessarily developing resistance to the cotton’s insecticide. Bollworms breed on corn, and last year more corn than usual was planted throughout cotton-growing regions. So it is likely that the cotton is simply being overwhelmed by corn-bred bollworms.
In evaluating the argument, which of the following would be most useful to establish?
B
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（结果的重申）
E: the concentration of histidine in the growing herb declines as the plant approaches maturit
c
不太明白....请帮忙解释一下咯...
两个题目的思路很相似，选项都是说该样本的特点在整个样本空间中是否具有普遍性。
通过比较，如果整个样本空间的单一样本都具有同样的特点，可support关于该特点的结论，如果不是，那么就关于该特点的结论就不一定成立
没明白。我还是选的D
请大家再讨论讨论。
D项至少是描述一个对结论有支持作用的现象。C说得是什么？其他很类似的herb也产生这种氨基酸。能说明什么？好牵强啊！
请NN指点。
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