Final answer:
The sampling method used when participants are selected according to a criteria set is stratified sampling.
Step-by-step explanation:
The sampling method used when participants are selected according to a criteria set is stratified sampling. Stratified sampling is a method for selecting a random sample that is used to ensure that subgroups of the population are represented adequately. In stratified sampling, the population is divided into groups called strata, and a proportionate number of individuals are randomly selected from each stratum.