In order to measure customer sentiment about mall security, Steven the stats intern was assigned to collect some data. He contacted the marketing offices of thefive main or anchor department stores. They in turn randomly selected 100 patrons from their store loyalty programs to be included in the sampling which would be conducted by e-mail, with incentives for completion.

Which statistical sampling technique best describes his methodology?

1. cluster sampling
2. convenience sampling
3. judgment sampling
4. network sampling
5. quota sampling
6. simple random sample
7. snowball sampling
8. stratified sampling
9. systematic sampling