How often does the boy play football?

The appropriate response indicates that the boy does not engage in playing football at all. This suggests a clear understanding of frequency terms, with "never" explicitly stating that the activity does not occur.

In this context, terms like "sometimes" and "rarely" suggest the boy plays football on occasion, while "often" implies a more regular participation. Therefore, selecting the answer indicating "never" effectively communicates the absence of any activity, aligning with the question's request for how often the boy plays football. This choice indicates a complete lack of involvement in the sport, which is the crux of the question being asked.