请问lsat13.2--24

chexplorina

The problem that environmental economics aims to remedy is the following: people making economic decisions cannot readily compare environmental factors, such as clean air and the survival of endangered species, with other costs and benefits. As environmental economists recognize, solving this problem requires assigning monetary values result from people comparing costs and benefits in order to arrive at economic decisions. Thus, environmental economics is stymied by what motivates it.
If the considerations advanced in its support are true, the passage’s conclusion is supported
(A) strongly, on the assumption that monetary values for environment factors cannot be assigned unless people make economic decisions about these factors
(B) strongly, unless economic decision-making has not yet had any effect on the things categorized as environmental factors
(C) at best weakly, because the passage fails to establish that economic decision-makers do not by and large take adequate account of environmental factors
(D) at best weakly, because the argument assumes that pollution and other effects on environmental factors rarely result from economic decision-making
(E) not at all, since the argument is circular, taking that conclusion as one of its premises
看了半天，不明白题干在说些什么，请大牛指教，谢谢！

zyh79

环境经济学目的就是要将环境因素与成本收益联系起来。
解决这一问题的前提：在做出经济决策之前给环境因素分派货币价值
那么，环境经济学将被其目的所阻碍。
假设说：在做出经济决策之前为不可能给环境因素分派货币价

chexplorina

谢谢版主指点，19题您也帮我解决了。真是大侠，佩服佩服！
我想这道题的重点是要理解in order to make economics decision和unless  ... make economics decision的矛盾关系，对吗？
另外，我申报了12.30--1.5的语法值周，已经会了确认信了，但还没收到回信，请您确认！