The statistical thinking underlying six signs is based on which of the following sets of principles.
A) all work activites can be done accurately most of the times empowered employees are needed for effective control and good statistical data is an empowered employee's best control tool.
B) all work is statistically controllable process 100% control is possible and very well controlled process is defect-free.
C) all activities can be controlled employee empowerment is the best control tool 100% control is possible.
D) all work is a process all processes have variability and all processes create data that explains variability.