Bonnie Conducts an Experiment to Examine the Effects of Media

Bonnie conducts an experiment to examine the effects of media on college women's body image. She gives a sample of women a body image questionnaire, then a week later exposes them to magazine photos of very thin models. Then a week later she administers a posttest designed to assess any changes in body image. Right before the posttest, a famous supermodel is reported to be suffering from anorexia; the story is on the cover of several magazines. Bonnie is concerned that the women's responses on the posttest may be influenced by the supermodel story instead of her independent variable. This example illustrates the potential problem of

A) mortality.
B) statistical regression.
C) selection.
D) history.