A Researcher Is Interested in Studying Attitudes About Raw Milk

Multiple Choice

A researcher is interested in studying attitudes about raw milk sales and has reason to believe that urban,suburban,and rural groups will vary in their responses.The researcher knows that the population being studied is 50% urban,40% suburban,and 20% rural.She classifies the potential participants as urban,suburban,or rural residents,and then,for a sample totaling 100,randomly selects 50 individuals from the urban group,40 from the suburban group,and 20 from the rural group.The researcher is using a(n) ____.

A) proportional stratified sample
B) balanced stratified sample
C) even stratified sample
D) primary stratified sample