Bradley, the manager of a home goods store wants to determine what items consumers are looking for this Christmas so that he can plan his orders. He decides to collect data for the purpose by stationing employees outside the store on a particular Saturday with a list of questions to ask willing shoppers to answer as they pass by$.$ In this case, the Bradley is using a $\_\_\_\_\_\_\_\_$Blank sampling method to select respondents.

Multiple Choice

probability

random

systematic

nonprobability

stratified