You have recently found that that several (many) data points have been recorded at or near (clustered around) the lower control limit (= 0) in an R-chart (range chart). Which of the following do you most agree with? The data points: suggests that no special cause of variation is present. should be investigated because a) the process has likely gone out of statistical control and b) a special beneficial cause of variation is likely present can be ignored because it signifies better than average quality. should be investigated because a) the process has likely gone out of statistical control and b) a special cause of variation is likely present that has to