Which of the Following Method(s)can Be Used to Determine If

Multiple Choice

Which of the following method(s) can be used to determine if nonresponse error is likely to be a problem in a particular study?

A) Contact a sample of nonrespondents.
B) Compare respondent demographics against known demographics of population.
C) Conduct an analysis of late respondents vs.early respondents.
D) All of the above.
E) None of the above.