Shown below is a control chart determined from attribute data. Given this chart and the plotted observations, the most appropriate action would be: ----- Upper Control Limit .06 Proportion Deflective 03 S Proportion Defective .03 ---- .02 x- t Mean Mean .01 .00 ---- 1 2 3 4 5 6 ------ Lower Control Limit 7 8 9 Sample Number Select one: a. take immediate action to identify the signaled causes of assignable variation. O b. do nothing since the process appears in control. O c. calculate the process capability index to verify it is less then one. O d. calculate the process capability index to verify it is greater than five. O e. take immediate action to identify the signaled causes of random (statistical) variation