ellen.li问道：
RC 2.111. The primary purpose of the passage is to
A. evaluate the likelihood that a particular proposal, if implemented, would ultimately succeed in
achieving its intended result
B. question the assumption that certain technological innovations are the most effective means of
realizing a particular environmental objective
C. discuss the progress of efforts to encourage a particular traditional society to adopt certain
modern agricultural methods
D. present the results of new research suggesting that previous findings concerning one set of
conditions may not be generalizable to another set of conditions
E. weigh the relative importance of three factors in determining whether a particular strategy will
be successful
我选择的答案是A，我认为文章中的是针对一个proposal在一些国家环境中的评价，而reserch只是提供了证据。但正确答案选D，为什么？
原文
One proposal for preserving rain forests is to promote the adoption of new agricultural technologies,
such as improved plant varieties and use of chemical herbicides, which would increase productivity
and slow deforestation by reducing demand for new cropland. Studies have shown that farmers in
developing countries who have achieved certain levels of education, wealth, and security of land
tenure are more likely to adopt such technologies. But these studies have focused on villages with
limited land that are tied to a market economy rather than on the relatively isolated, self-sufficient
communities with ample land characteristic of rain-forest regions. A recent study of the Tawahka
people of the Honduran rain forest found that farmers with some formal education were more likely
to adopt improved plant varieties but less likely to use chemical herbicides and that those who
spoke Spanish (the language of the market economy) were more likely to adopt both technologies.
Nonland wealth was also associated with more adoption of both technologies, but availability of
uncultivated land reduced the incentive to employ the productivity-enhancing technologies.
Researchers also measured land-tenure security: in Tawahka society,kinship ties are a more
important indicator of this than are legal property rights, so researchers measured it by a
house-hold’s duration of residence in its village. They found that longer residence correlated with
more adoption of improved plant varieties but less adoption of chemical herbicides.
