A Queens College student conducted an experiment to evaluate the effectiveness of different stress relief methods on level of stress in Psychology students. The first group was asked to exercise, the second group was asked to meditate, and the third group made no changes when experiencing high levels of stress. The students were asked to record their stress levels before and after treatment. What is the dependent variable for this study? a. Stress relief method. b. Stress level. c. Psychology students. d. Queens College.