A clinical study was conducted on the effectiveness of a new knee surgery to cure a specific type of arthritis. Of the 219 individuals who met the inclusion criteria, 114 declined to participate. The researchers randomly divided the remaining 105 subject into three groups: One group received type A knee surgery; and the second group received type B knee surgery; a third group received skin incision to make it.look like they had received knee surgery, but no actual surgery was performed. The patients in the study did not know which group they were in and in particular did not know if they were receiving the real surgery or simulated surgery. In a two-year follow up, all three groups said they had slightly less pain and better knee movement, but the "fake" surgery group often reported the best results. Which of the following represents the target population for this study. All potential knee surgery patients who met the inclusion criteria. The 105 subjects who participated. The 219 individual who met the inclusion criteria for the study? The subjects who fell into the two treatment groups (not those in the third group for whom no actual surgery was performed).