Sociologists at the University of Chicago Have Been Giving the General

Sociologists at the University of Chicago have been giving the General Social Survey (GSS) every year or two since 1972. A key benefit of this type of survey is that

A) it does not require a random or representative sample.
B) it allows researchers to identify changes in attitudes over time.
C) it increases honesty by having people give answers directly to interviewers.
D) the questions are always evolving to reflect changing attitudes about sex.
E) the design includes multiple control groups.