A medical journal published the results of an experiment on anorexia. The experiment investigated the effects of a controversial new therapy for anorexia. Researchers measured the anorexia levels of 91 adult women who suffer moderate conditions of the disorder. After the therapy, the researchers again measured the women's anorexia levels. The differences between the the

and

anorexia levels were reported. Identify the experimental units.
◦ the differences between the pre- and post-therapy anorexia levels
◦ the 91 adult women who suffer from anorexia
◦ the therapy time period (pre or post)
◦ the disorder (anorexia or no anorexia)