Respuesta :
Answer:
Stratified sampling
Step-by-step explanation:
key word "groups"
The sampling scheme did she used is stratified sampling.
What is stratified sampling?
It is a method of sampling where the division of the population should be split into the smaller subgroup called a strata. The strata should be created depending upon on the members shared like the income etc. Here the sample should be needed for applicants for across the US also it randomly selects the applicants for each state.
So, The sampling scheme did she used is stratified sampling.
Learn more about a sample here: https://brainly.com/question/24526520