Which emotion is most characteristic of withdrawn children?

Bipolar disorder in the U.S. is found to be comorbid with __________

A) schizophrenic disorders B) personality disorders C) substance abuse D) phobic disorder

The Solomon four-group design allows a researcher to measure ______.

a. all confounding variables that may be present b. the effect of taking the pretest on the scores on the posttest c. group differences between the control and experimental groups d. the causal effect of the treatment