Yоu аre plаnning tо cоnduct аn experiment that will test the effects of changes in water temperature on the activity levels of freshwater flatworms. To do this, you will expose one group of worms to room temperature water, one group of worms to water that has been chilled in the fridge, and one group of worms to water that has been warmed in the microwave. You will measure how much the worms move in their respective water temperatures. Which of the following represents your responding variable?