问另一道jj cr答案

jillgu

  1# GWD：
   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D请问nn们答案是多少啊

wezard

以下是引用jillgu在2007-7-29 14:18:00的发言：

  1# GWD：
   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D请问nn们答案是多少啊

答案应该是C。

注意，原题中说道，这种herb是一个group里面的，这个group的植物生长在有重金属的土里。科学家在herb里面发现了某种物质，所以推测，正是因为有这种物质，所以herb才能在重金属的土壤里面生长。那么最好的support就是C了，在同group的其他植物中也发现了该种物质。这就是基本的“有因（同种物质）有果（都生长在重金属土里）”模型。

至于D，不能说明能够生长在重金属的土里是因为有这种物质，反而给出了他因，其实是weaken了原文的假设。

jillgu

知道了谢谢啊

victer

这题在CD上也有很大的争议，我倾向于选D，但是我也不是nn，也不敢肯定自己想的就是对的。所以我也不在这里废话了，希望LZ还是自己搜一下前人nn的讨论，呵呵~~~~~

希望大家都好运啦！！