The General Social Survey (GSS), conducted by the National Opinion Research Center at the University of Chicago, is a major source of data on social attitudes in the U.S. Once each year 1500 American adults aged 18+ are interviewed in their homes all across the U.S. The subjects are asked their opinions about sex and marriage, attitudes toward women, welfare, foreign policy and many other issues.
The implied population is
a- All Americans.
b- All American adults.
c- All people worldwide.
d- the 1500 randomly chosen adults.