A Researcher Who Wants to Conduct a Study in the Local

Multiple Choice

A researcher who wants to conduct a study in the local high school finds that she must use volunteers rather than intact class groups.In this case, the researcher should

A) make sure to use a sample of at least 30 or more subjects.
B) control for the subjects' willingness to volunteer.
C) keep the volunteer subjects naive as to the purpose of the study.
D) determine the extent to which volunteers may differ from nonvolunteers on important variables.