Question ID:PT88 S2 Q21 Passage:A study of 30 years of weather pattern records of several industrialized urban areas found that weekend days tend to be cloudier than weekdays. Thus it can no longer be denied that human activity has appreciable, large-scale effects on weather, because the few seven-day cycles that occur naturally are of too little significance to cause measurable weather patterns. Stem:Which one of the following is an assumption on which the argument depends? Correct Answer Choice:EChoice A:Industrial activity tends to decrease significantly on weekend days in the large urban areas studied. Choice B:There are no naturally occurring seven-day cycles in the areas studied. Choice C:If living organisms have an appreciable large-scale effect on weather patterns, then this is due at least partly to the effects of human activity. Choice D:If something appreciably affects large-scale weather patterns, it is probably cyclical in nature. Choice E:If a weather pattern with a natural cause has a seven-day cycle, then that cause has a seven-day cycle.