DrJohansen Randomly Assigned Subjects to Three Different Groups During Her

Multiple Choice

Dr.Johansen randomly assigned subjects to three different groups during her last experiment.She then proceeded to give all the participants in the experiment a new study technique designed to enhance their learning for the upcoming test.What critical error did she make during her experiment?

A) She failed to identify the independent variable.
B) She failed to identify the dependent variable.
C) She failed to include an experimental group.
D) She failed to include a control group.