In the following situation, which test should be used? Independent variable = educational status (high school diploma vs. Bachelor's degree vs. graduate degree); dependent variable = frequency of insomnia (1 = never, 2 = 1-5 times/year; 3 = 6-10 times/year; 4 = 11-25 times/year; 5 = 25-49 times/year; 6 = 50 times/year) Question 9 options: Chi-square test Kruskal-Wallis test Cochran's Q McNemar test