Just ticking the box is fine...no problem, Norah.
It is when it comes to counting "obstacles" that "the thing" and I tend to disagree.....!
Perhaps I might do better if I WERE a robot!
Elle, a little tip from one used to Captchas...
Even if the 'object' is only just inside its box by a pixel or two, it still counts as being there. Fire hydrants passed !