Dr. Torres discovers a new drug that he hypothesizes will decrease fat storage in mice. He designs an experiment to test his hypothesis. Dr. Torres separates twelve mice into two equal groups and measures their body fat individually. He gives one group of mice the drug but does not give the drug to the other group. He keeps everything else about the mice's living environment the same, including the amount of water and food provided. After a month, he measures the body fat of the mice in both groups. The group of mice that is not given the drug is known as the control. Why do scientists use controls when designing experiments? A. At the end of the experiment, only the control data is analyzed and reported in order to determine if the factor had the hypothesized effect. B. The control data is not important for most kinds of experiments, is not ever analyzed, and is usually discarded at the end of an experiment. C. At the end of an experiment, the control group is compared to the experimental group in order to determine if the factor had the hypothesized effect. D. The control data is only analyzed if the experimenter makes a mistake while recording data from the experimental group and needs extra data.