Researchers conducted a study to determine whether magnets are effective in treating back pain. Pain was measured using the visual analog scale, and the results given below are among the results obtained in the study. Higher scores correspond to greater pain levels. Is this study an experiment or an observational study? Explain. Reduction in Pain Level After Magnet Treatment: nequals20, x overbarequals0.489, sequals0.958 Reduction in Pain Level After Sham Treatment: nequals20, x overbarequals0.443, sequals1.38 Question content area bottom Part 1 Choose the correct answer below. A. The study is an observational study because the subjects are a simple random sample. B. The study is an experiment because the subjects are a systematic sample. C. The study is an experiment because subjects were given treatments. D. The study is an observational study because there was no attempt to modify the individuals being studied