Final answer:
The type of sampling used when a researcher questions students leaving an athletic facility is convenience sampling, as it is based on the accessibility of individuals rather than random selection.
Step-by-step explanation:
The type of sampling being used when a researcher questions students as they leave an athletic facility about their dating habits is convenience sampling. This is because the researcher is choosing individuals who are easily accessible and available at the time of the study rather than using a methodology that seeks to randomly select participants or use a more structured method like stratified sampling. Convenience sampling is often used when it is not feasible to do random or systematic sampling due to constraints such as time, cost, or other practical considerations.