state the type of study described below, a study of 3000 last years cell phone contracts identified those with a text messaging plan and those without a text messaging plan. Choose the correct answer below. A. The study is a single-blind experiment. B. The study is a double-blind experiment. C. This is an observational study that is neither retrospective nor prospective. D. The study is an experiment with no blinding. E. This is an observational, prospective study. F. This is an observational, retrospective study.