Imagine a study in which a researcher is interested in reducing anxiety. All participants are measured on anxiety (using a set of survey items). Then, each . participant interacts with a very friendly dog. Anxiety is measured again after the dog is removed. In this case, because we anticipate a reduction in anxiety, what should we do with the two measures of anxiety? O A) .. multiply the pretest by the posttest (i.e., pretest times posttest) (B) .. take the ratio of the pretest to the posttest (i.e., pretest divided by posttest) ( C) ... take the ratio of the posttest to the pretest (i.e., posttest divided by pretest) OD) ... subtract the posttest from the pretest (i.e., pretest minus posttest)