Let's say that you have two sets of performance data on two divisions in your company.

Which statement is the MOST accurate?

A) A mean performance difference can never improve the performance comparison between the two divisions.

B) The "mean difference" in performance of the two divisions is sufficient to tell us which one is the better performer.

C) A mean performance difference in the two divisions is only sufficient if the sample size in performance observations for both divisions is also high and the standard deviation in performance for both divisions is also low.