Answer: a) the type of exposure to Geomyces destructans; whether the bats became sick with WNS
Explanation: The independent variable refers to the variables employed by the experimenter to use as a tool to observe changes in the dependent variable. In an experimental study, the independent variables are usually the different controls adopted for the experiment. In the scenario above, the independent variable is the type of exposure to Geomyces destructans which each of the groups are exposed to. These variation in control in which the different groups are exposed to may result in different response within the group which is the change in WNS. These response due to exposure to different control is called the dependent variable.
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