Which of the following is true with regard to mail questionnaires?
A) The response rate of mail questionnaires is often very low.
B) Mail questionnaires are highly flexible.
C) The researcher has maximum control over the mail questionnaire sample.
D) Mail questionnaires are unsuitable for collecting large amounts of information about respondents.
E) Respondents always provide honest answers to personal questions on mail questionnaires.
Answer: The response rate of mail questionnaires is often very low.