lol! The missing "submit" and only a "reset" button also drove me nuts!!! That page actually does some javascript code, which is not currently working. (you can see this when you click on one of the options while in console/devtools).

Its a ruse, they just want you to look at random people's backside and think that it's a elbow. The modern day version of scanning your ass and printing it lol

From the source: false, true, true, false, true, true, false, false, true, true, true, false, true, false (go left to right, top to bottom)