Which of the Following Situations Suggests a Process That Appears

Multiple Choice

Which of the following situations suggests a process that appears to be operating out of statistical control?

A) a control chart with a series of consecutive points that are above the center line and a series of consecutive points that are below the center line
B) a control chart in which several points fall outside the upper control limit
C) a control chart in which points fall outside the lower control limit
D) all of the above