6. It can be inferred from the passage that which of the following plant species would be LEAST likely to experience a decrease in fecundity as a result of the spraying of a pesticide not directly toxic to plants？
（A） A flowering tree pollinated by only a few insect species
（B） A kind of insect-pollinated vine producing few flowers
（C） A wind-pollinated flowering tree that is short-lived
（D） A flowering shrub pollinated by a large number of insect species
（E） A type of wildflower typically pollinated by larger insects
7. Which of the following assumptions most probably underlies the author’s tentative recommendation in lines 51-54？
（A） Human activities that result in environmental disruption should be abandoned.
（B） The use of pesticides is likely to continue into the future.
（C） It is economically beneficial to preserve endangered plant species.
（D） Preventing the endangerment of a species is less costly than trying to save an already endangered one.
（E） Conservation efforts aimed at preserving a few well-chosen species are more cost-effective than are broader-based efforts to improve the environment.
参考答案：CADA ACB
