A purposive sample of psychology graduate students finishing up their dissertation at one online university (n = 80), one public brick-and-mortar university (n = 35), and one private brick-and-mortar university (n = 20) rated overall satisfaction with their dissertation chair using a scale of 0 (completely dissatisfied) to 100 (completely satisfied). Each university had 100 students finishing up their dissertation. The mean satisfaction ratings were: online = 83.5, public brick-and-mortar = 92.7, private brick-and-mortar = 90.3. The standard deviations were equal. Which of the following pairwise comparisons of mean ratings would have the smallest effect size?
a. Public versus private
b. Public versus online
c. Online versus private
d. The effect size of each pairwise comparison would be equal