Well, they were certainly not expecting people of our intellectual calibre to respond.
Now here's one for you Mensa-types: if you can find the solution to this most difficult of puzzles (just the answer and not even the reason) in under fifteen minutes, you are positively Einsteinian: less than one-thousandth of one-percent of all those who try succeed.
(Oops, I nearly forgot the question here):
Which one square/configuration is totally erroneous when compared with any sequence (horizontal, vertical or diagonal) of nine successive other squares?
Just one rotten apple, so to speak....
I've explained it in my usual imprecise way, but good luck just the same: I know some of you guys can do it!
(Like I said, first one to find the answer in under fifteen minutes - or ever - is a freaking genius).