Which of the Following Statements Is Best Regarding Process Variation

Multiple Choice

Which of the following statements is best regarding process variation?
I. All variation is due to chance.
II. Random variation is inherent in the process.
III. Assignable variation is due to a specific cause.

A) I and II are true
B) I and III are true
C) II and III are true
D) I only is true
E) II only is true