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. Ttherefore, provided this technology is effective, the fears are groundless. Which of the following, if true, most seriously weakens the argument? ["Changes in land use and drainage patterns around the lake mean that the lake's waters are increasingly likely to be affected by agricultural runoff.", "The pipeline's construction will disturb sediments at the bottom of the lake, dispersing into the water toxic pollutants that have settled there.", "A major leak of oil from the pipeline would harm not only the lake's fish but also populations of other aquatic animals and plants.", 'The leak-preventing technology has been in use for several years without any pipeline in which it is installed developing serious leaks.']