Determine whether the following study is an observational study or an experiment. If the study is an experiment, identify the control and treatment groups, and discuss whether single- ordouble-blinding is necessary. If the study is observational, state whether it is a case-control study, and if so, identify the cases and controls. In a study done at a university, researchers took snapshots of 4300 white adults every four years for 28 years and determined that 9 out of 10 men and 6 out of 10 women will eventually become overweight. Choose the correct answer below.

A. Observational study; case control; the cases are the adults that became overweight, the controls are the adults that did not

B. Experiment; the control group is the men, the treatment group is the women; not blinded

C. Experiment; the control group is the adults who did not become overweight, the treatment group is the adults that becameoverweight; single blind

D. Observational study; not case-control

E. Experiment; the control group is the adults who did not become overweight, the treatment group is the adults that became overweight; double blind