GWD-28-28

carmenleaf

28-28: 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

看见贴出来的答案都是选D和E的，但我怎么觉得选C呀，大家怎样看？

howardwang

本来就该是C,你的感觉没错。

carmenleaf

谢谢howardwang帮我确定。

spencer06

what is gwd 28?

I Only have gwd 1-13 and 24. Do you have new articles about GWD

If you don't mind, plz send me what you have new gwd !!!!

It will be very good to me.

Thanks in advanced...

jaewonyoo@hanmail.net

liubin1987

我也选C

但看了很多讨论,似乎都各执一词