Mr$.$ Sam Pull is about to launch a new brand of high fat potato chips and wants to conduct market research with $500$ consumers across the U$.$S$.$ However to take a sample of individuals across the U$.$S$.$ would be too costly because he would have to spread out the sample collection across the whole U$.$S$.$ He refuses to use any sampling technique that is not based on chance. From the list below, please choose the best type of sampling technique for Sam.

judgment sampling

convenience sampling

quota sampling

cluster sampling

stratified sampling