Administrators at a university were interested in estimating the percentage of students who are the first in their family to go to college. The university student body has about 43,000 members. For each scenarios a through c, identify the kind of samples used by the university administrators.
a) Select several dormitories at random and contact everyone living in the selected dorms. Choose the correct answer below.
O stratified sample
O systematic sample
O cluster sample
O multi-stage sample