If I had to guess it would be hoops as there are just too many people playing football and there are some dog bettors there and bases is the sport you hear that you have to bet dogs (though this would be my 2nd choice) as favorites supposedly will kill you but I am not 100% sure most people have heard this.
This leaves hoops where I think most think there bet will be up late, get fouled and make their free throws, covering the spread. That is how most of us play it out in our mind.