Which of the Following Is an Example of Special Cause

Multiple Choice

Which of the following is an example of special cause variation?

A) Yesterday the framing crew was a little tired and didn't get as much done as they thought.
B) The avian flu ravaged the laying stock for Chickenverks and the Great Egg Shortage of '06 threatened to cancel Easter egg hunts worldwide.
C) The product unveiling was a week late because there was some difficulty getting the ivory through customs.
D) The debugging step averages two months but this project was finished a day early.