问一题prep上的题

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

为什么 不清楚题目想要问的是什么，为了避免过多的限制性的管制，然后呢？

还有 pp3 是什么与prep不同吗？在哪里有得下？

为了环保各国同意统一控制排放物的量，不管某一环境破换现象是否归因于某一特定排放源。但是为了避免过度控制，必须怎样？

B任何需要控制的物质必须是能够导致环境破坏的。namely, no damage, no control needed.

pp3是模考套题软件  下载区没有吗？