Translation:She teaches her dog to fetch the newspaper.
There can be more than one correct solution. I think by showing "her dog" as the default solution, they're trying to indicate that hunden doesn't always have to be "the dog", it just always has to be definitive, so one dog in particular, and "her dog" works equally well.
I agree it's a bit confusing the first time.
I have the same question. Why isn't the correct translation Hon lär hunden att hämta tidningen. Is lära one of those verbs that doesn't require the infinitive marker att or is the att optional? Another related question: Hon lär hunden hämta tidningen. was accepted as correct, but as I read through my Routledge Swedish Dictionary, I see that to teach someone something the construction should be lära ut. This point was discussed at the top of this discussion. So, if I understand Arnauti's comment, ut is not required here because 'the something' being taught is 'hämta tidningen' which is not a noun. So lära by itself is synonymous with träna = to train (or perhaps utbilda) Am I getting close to understanding this?