请高手帮忙看一个选项 OG11 CR 10题

　　At a recent conference on environmental threats to the North Sea， most participating countries favored uniform controls on the quality of effluents， whether or not specific environmental damage could be attributed to a particular source of effluent. What must， of course， be shown， in order to avoid excessively restrictive controls， is that ___________.

　　（A） any uniform controls that are adopted are likely to be implemented without delay

　　（B） any substance to be made subject to controls can actually cause environmental damage

　　（C） the countries favoring uniform controls are those generating the largest quantities of effluents

　　（D） all of any given pollutant that is to be controlled actually reaches the North Sea at present

　　（E） environmental damage already inflicted on the North Sea is reversible

答案选B

其他几个选项为什么不对 我明白。

但是B选项读不懂 请高手帮忙解释一下。可能是substance的用法不了解。

在此谢过啦~~~~

对B取反，存在至少一个与control相对的substance，不会真的造成environmental damage，那么显然restrictive controls会过度，削弱原文结论，因此选B