Design patterns for finding a match

Need assistance in structuring my code with design patterns.

So I have a single method in service class that looks like this. The constructor loads a json file into a List<Option> of Option class instances. Finally when the service method is called it does some logic to find the Option match based on the parameter values and returns a new instance of 'Tool' class with the configured "options".

public Tool BestOptionFinderService.FindBestMatch(string value 1, int value2, int value3, .. bool value20, etc...) {..}

I'm not sure if I a "service" class is correct for this versus a "factory" or something else. I would appreciate your thoughts and suggestions on how you would design your code for this problem or similar.