Statistics
posted by Pat on .
To make causal inferences from observed differences between groups based on varied levels of treatment, it is necessary to...?
A. Find significant differences between groups at atleast the .05 level
B. Use Ttest or ANOVA procedures to conduct the analysis
C. Have random assignment of participants to treatment levels and control conditions as a basis of design, prior to conducting analysis
D. Deploy at least a quasiexperimental design

C.