Early in the twentieth century, Lake Konfa became very polluted. Recently fish populations have recovered as release of industrial pollutants has declined and the lake's waters have become cleaner. Fears are now being voiced that the planned construction of an oil pipeline across the lake's bottom might revive pollution and cause the fish population to decline again. However, a technology for preventing leaks is being installed. Therefore, provided this technology is effective, those fears are groundless.
The argument depends on assuming which of the following?
Early in the twentieth century, Lake Konfa became very polluted. Recently fish populations have recovered as release of industrial pollutants has declined and the lake’s waters have become cleaner. Fears are now being voiced that the planned construction of an oil pipeline across the lake’s bottom might revive pollution and cause the fish population to decline again. However, a technology for preventing leaks is being installed. Therefore, provided this technology is effective, those fears are groundless. The argument depends on assuming which of the following? A. Apart from development related to the pipeline, there will be no new industrial development around the lake that will create renewed pollution in its waters. B. Other than the possibility of a leak, there is no realistic pollution threat posed to the lake by the pipeline’s construction. C. There is no reason to believe that the leak-preventing technology would be ineffective when installed in the pipeline in Lake Konfa. D. Damage to the lake’s fish populations would be the only harm that a leak of oil from the pipeline would cause. E. The species of fish that are present in Lake Konfa now are the same as those that were in the lake before it was affected by pollution. C为什么不对!!??
首先,答案必然是B 选项B说,建造pipeline的唯一可能的对水源的污染就是泄露。原文中说,provided this technology is effective,即唯一的由于建造pipeline所能导致的污染也可以被控制。所以逻辑成立。 GWD说,不要管到底是假设还是增强,一切正向评价均是使得原文中结论的置信度的增加。
既然有人讨论了A、C,我也说一下这两个答案 选项A说,除了与建造pipeline相关的发展以外,没有其他的污染源 确实,这也是水源不被污染的前提条件之一,但是,请注意原文讨论的内容,是Fears are now being voiced that the planned construction of an oil pipeline across the lake’s bottom might revive pollution and cause the fish population to decline again。说明,一切原文的讨论时围绕建造pipeline展开的,既然fears只是关于pipeline的,那么其他的建造就应被默认为没有影响(狒狒说,一定要明白原文再讨论的核心是什么,跟核心无关的统统是错误选项) 选项C说,防漏措施并不一定有效。注意原文明确提到 Therefore, provided this technology is effective, those fears are groundless.说明,结论(Therefore之后的内容)是一个有条件的结论,条件(provided)之后的内容若成立,则fears are groundless。因而,如果否认条件,是并不能否认结论的。即如果provided的内容不存在,则根本无法对结论的真实性进行判断(因为没有结论存在的前提,所以结论根本就不存在)。用狒狒的话说就是不能否认原文的内容。(说句题外话,我觉得GWD确实比狒狒技高一筹)