注意：GWD-28-28答案很可能有误。。。。。。

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 ______.

1. histidine is found in all parts of the plant—roots, stem, leaves,
        and flowers
2. the herb’s high level of histidine production is found to be
        associated with an unusually low level of production of other amino acids
3. others of the closely related group of plants are also found to
        produce histidine in large quantities
4. 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
5. the concentration of histidine in the growing herb declines as the plant
        approaches maturity

另外，顺便问一下这道题：答案为c. nn  们能给我讲讲e是啥意思，以及为什么不对吗？Q7:

In 1960’s studies of rats, scientists found that crowding
increases the number of attacks among the animals significantly.  But in recent experiments in which rhesus
monkeys were placed in crowded conditions, although there was an increase in
instances of “coping” behavior—such as submissive gestures and avoidance of
dominant individuals—attacks did not become any more frequent.  Therefore it is not likely that, for any species
of monkey, crowding increases aggression as significantly as was seen in rats.

Which of the following, if true, most
strengthens the argument?

1. All the observed forms of coping behavior can be found among
        rhesus monkeys living in uncrowded conditions.
2. In the studies of rats, nondominant individuals were found to
        increasingly avoid dominant individuals when the animals were in crowded
        conditions.
3. Rhesus monkeys respond with aggression to a wider range of stimuli than
        any other monkeys do.
4. Some individual monkeys in the experiment were involved in
        significantly more attacks than the other monkeys were.
5. Some of the coping behavior displayed by rhesus monkeys is similar to
        behavior rhesus monkeys use to bring to an end an attack that has begun.

答案应该不是d也不是e吧，是c呀

d和a都是某种程度的重复原文，虽有加强作用但不及C,且C中others of the closely related group of plants与原文one of a group of closely related plants 对应

另一题e讲的是r猴在crowded conditions情况下表现出的coping behavior和他们用来结束attack时的动作相似，也就解释了为什么他们不常attack，但并没有争对原文结论，尤其是any species of monkey。

NO.1 C应该是加强阿，其他和herb同类（能在此种土壤生存）的植物也含有大量histidine ,不正说明herb是通过histidine起作

     用的吗？！

NO.2 E说还没怎么开始打假就结束了，怎么会是爱打假呢？

有没有注意到C的绿色部分呢？根据题干第一句话，这个closely related group of plants是指能在重金属土壤生存的植物，他们含h,而herb也能在重金属土壤生存，herb也含h，说明herb的h就是原因阿。这不是很好的加强吗？怎么就排除了？

不对吧，这个意思是多想出来的，难道成熟了就不需要吸收土壤成分了？这些是不得知的！

毫无疑问D.

C与文中讨论的使金属钝化的作用无关。D说明正式H的钝化作用使土地适于生长植物。

C, this one is easy, dont get urself confused, "the closely related group of plants" in C refers to the "a group of closely related plants" which includes that herb. So typical "same cause, same effect" strenghen

Q28应该选D。C选项说的是others of the closely related group of plants，是个无关项。

Q7的答案给的正确，选C。C选项说明，这种猴子已经比其他任何一种猴子容易respond with aggression，而argument说这一种猴子在试验中没有表现出increased aggression，正好加强了结论。