Choose the correct answer below.

A$.$

The move to voluntary completion of the more detailed form introduces response bias. The households that receive the extra form have the opportunity to be counted multiple times and end up overrepresented in the results.

B$.$

The move to voluntary completion of the more detailed form introduces nonresponse bias. Since the survey is$$ longer, very few households if any will elect to complete it instead of the Short$$ Form, severely impacting the results.

C$.$

The move to voluntary completion of the more detailed form introduces voluntary response bias. In$$ particular, since disadvantaged households may choose not to complete the$$ form, the results may underrepresent those groups in Canadian society.

D$.$

The move to voluntary completion of the more detailed form adds validity to the census. In$$ particular, people who provide inaccurate answers out of spite from being forced to participate will no longer be factored in$.$