"Modern és hasznos? Az nem lehetséges."
Translation:Modern and useful? That is not possible.
The suggested English translation doesn't make a complete sentence. It should be "Is it modern and useful?". Right?
It's as much half a sentence as the Hungarian translation. More an exclamation of surprise than an actual question.
It could, but the version with 'that' is closer to both the Hungarian translation and the intended feeling/expression. Usually I would translate "It is not possible" simply with "Nem lehetséges."