Being from Cincinnati, I had to laugh at that particular example a little bit, because there's an annual charity "Rubber Duck Regatta" where you pay to sponsor a rubber duck and they dump them all in the river and give a prize to whoever has theirs finish first. When I was a kid, they ran TV ads for it blasting the name out loud about every six seconds, so most students who didn't know the word otherwise would have figured it out. I'm sure there would be statistical analysts looking at the scores for that question by region and scratching their heads.