Answer:
Causal-comparative
Step-by-step explanation:
Based on the scenario being described within the question it can be said that the type of research method that Ken is employing is known as Causal-comparative. This term refers to a research design which focuses on trying to find the unique relationship that may exist between the independent and dependent variables, but only after a certain event has taken place. Which in this scenario the event would be the prior football experience.