When faced with a situation that involves comparing each group in a research study with a single reference group, which method for controlling familywise error would be most appropriate?

A) complex comparison
B) Scheffé Test
C) Tukey Test
D) Dunnett Test

The Dunnett Test is specifically designed for situations where multiple groups are being compared to a single reference group. It controls the familywise error rate by adjusting the alpha level for each comparison in order to maintain an overall alpha level for the entire set of comparisons. The other methods listed (complex comparison, Scheffé Test, and Tukey Test) are not designed specifically for this type of situation and may not provide adequate control of familywise error.