I think in real life, these captchas often accept your answer in both cases, in the case of ambiguity.
These captchas often don't actually have the answer included - they're collecting the answers so they can train bots in object recognition. They take your answer and compare it to a bunch of near simultaneous answers from other people, then accept it if it's close to what other people are saying.
cuuuute!
also, do I select the box where there is only a horse tail? It has a horse in it but it's not a lot of horse...
I think in real life, these captchas often accept your answer in both cases, in the case of ambiguity.
These captchas often don't actually have the answer included - they're collecting the answers so they can train bots in object recognition. They take your answer and compare it to a bunch of near simultaneous answers from other people, then accept it if it's close to what other people are saying.
This is true!
So to answer “Do I select one that only has its tail?”, it depends on what most people pick, so just trust your gut feeling.