A researcher discovers that in a particular city 10% of the households are headed by a single person and that 90% of the families are husband-wife families. The researcher tells interviewers to conduct 80 interviews. Ten percent of these interviews should be with families that are headed by a single person, and 90% should be with husband-wife families. This research uses
simple random sampling
I feel like it could be b but I am unsure. Anyone?