Which of the following statement on ANOVA is correct when the F-test is significant?
A. We can conclude that the group with the biggest mean is significantly different from the other groups.
B. We can conclude that the means of all the groups are significantly different.
C. We can conclude that at least two means are significantly different from the others but do not know which are the two means.
D. We can conclude that at least one mean is significantly different from the others but have to conduct a post-hoc test (e. g. Bonferroni correction) to determine which mean(s) is/are significantly different from the others.