There are 3 others, but unlike every other site, it doesn't let you pick. This is the one I got when I just logged on.
WHAT IS YOUR FAVORITE MUSICAL INSTRUMENT?
LUTE
6-STRING GUITAR
DIDGERIDOO
BANJO
PIANO
BAGPIPE
12-STRING GUITAR
TROMBONE
ORGAN
DRUMS
I'm an idiot American so I had to Google because I was sure they mispelled Flute, which would be a terrible choice because nobody's favorite instrument is the flute.
There's some guitar looking thing from England that was popular in the 16th century. When I saw a pic, I've seen them in movies but I would have never know the shit was called a Lute. Yes I'm not cultured, I'm sure 99% of ATOTers will know Lute. Pretty sure the average person who has an account won't know either. And a Didgeridoo? I mean I know what the hell those are, but I don't think anyone picked that. I can't see any conversation ever starting with the phrase "you know, my favorite instrument gotta be a Didgeridoo." But I'll admit I'm far from a Didgeridoo, so maybe it's not just an instrument Aboriginal people use to play. Hipsters love to love weird shit so maybe this is a viable answer for people.
I think they used some AI program and let it choose the answers.