Question ID:PT59 S3 Q12 Passage:To cut costs, a high school modified its air-conditioning system to increase its efficiency. The modified system, however, caused the humidity in the school air to decrease by 18 percent. Twenty-four hours after the decrease in air humidity, a 25 percent increase in the number of visits to the school nurse was reported. This shows that a decrease in humidity can make people ill. Stem:The argument depends on assuming which one of the following? Correct Answer Choice:AChoice A:At least some of the visits to the school nurse after the system was modified were due to illness. Choice B:Most of the students at the high school suffered from the decrease in air humidity. Choice C:It takes 24 hours after a person is infected with a virus for that person to exhibit symptoms. Choice D:A decrease of 18 percent in air humidity causes an increase of 25 percent in one's probability of becoming ill. Choice E:Modifying the air-conditioning system proved to be an ineffective way to cut costs.