To estimate the prevalence of breast cancer among adult women in Guangzhou city, a research institute randomly selected 50 communities out of all communities in Guangzhou, and then investigated all adult women in each selected community. What sampling method was used in this survey?
A、Clustersampling;
B、Systematicsampling;
C、Stratifiedsampling;
D、Simplerandomsampling;
E、Non-randomsampling
发布时间：2024-09-27 13:56:31
