Researchers wanted to determine if having a video game console in the bedroom is associated with obesity. the researchers administered a questionnaire to 353 ​twelve-year-old adolescents. after analyzing the​ results, the researchers determined that the body mass index of the adolescents who had a video game console in their bedroom was significantly higher than that of the adolescents who did not have a video game console in their bedroom. complete parts​ (a) through​ (e) below. ​(a) why is this an observational​ study? what type of observational study is​ this? why is this an observational​ study? a. the researchers administered a questionnaire to obtain their data without trying to influence an explanatory variable of the study. your answer is correct. b. the researchers intentionally changed an explanatory variable of the study. c. the researchers tried to influence the outcome of the study. d. the researchers observed the behavior of the individuals in the study without trying to influence an explanatory variable of the study. what type of observational study is​ this? cohort study ​case-control study ​cross-sectional study