You conduct an ANOVA at the .05 error level and find a significant F . You conduct a Tukey HSD post hoc test on the same data at the same .

You conduct an ANOVA at the .05 error level and find a significant F. You conduct a Tukey HSD post hoc test on the same data at the same .05 error level and find no significant difference between the particular groups. From these results, you know that:

the sample size in each group was not sufficient to pick up the effect detected by the F test

the variation within each group masked the variation between the groups

you should have conducted your Tukey HSD at the .01 error level

you have made a calculation error in either the F test or the Tukey HSD