Which of the following are indicators of out-of-control conditions on a control chart, except?

The selected option indicates an out-of-control condition on a control chart. The scenario presented—two points in zone C above the mean followed by two points in zone B below the mean—suggests a pattern that may signify an instability in the process. Out-of-control conditions are typically indicated by specific patterns or points on a control chart that signal potential problems with the process being monitored.

In contrast, a single point falling outside the control limits signifies a clear deviation from the expected range of variation, which is a strong indicator of an out-of-control condition. Similarly, five consecutive points in one direction (indicating a trend) also signal process instability. Those scenarios are each clear indicators that a process may not be under control.

Two points in zone A, on the other hand, suggest the points are still within the control limits, indicating that while the process may experience variation, it does not necessarily imply out-of-control conditions. The presence of points in zone A alone does not provide sufficient evidence to decisively label the process as out-of-control, thereby supporting the argument for why this would not be an indicator of such conditions.