"These beautiful pictures are on the wall."
Translation:Ezek a szép képek a falon vannak.
I think the best thing to do is submit a free-form report complaining about such mandatory alternatives with non-taught words. (They also show up frequently with szálloda + hotel.)
I think what the course maintainers have to do is remove the non-taught words from the translations marked "best" and include them as a separate alternative that is not marked "best", since I believe the multiple-choice sentences are drawn only from the alternatives that are marked "best". (Those have a blue star in the incubator interface.)