7. A clinical trial is conducted in order to assess the effectiveness of a new cancer drug, and several cancer patients agree to take part in the study. The study compares the cancer drug to a placebo, and a published report about the study claims the study was double-blind. What does it mean if a study is double-blind? A. All individual data recorded as part of the study is kept confidential. B. Although the researchers who were conducting the study were told which treatment each patient received, they were forbidden to share this information with the patients. C. The patients were told which treatment they received, but they were forbidden to share this information with the researchers who were conducting the study. D. The researchers who were conducting the study did not know who was receiving which treatment and neither did the patients. E. The researchers who were conducting the study were not allowed to talk publicly about their involvement in the study, nor were the patients allowed to talk about this