All languages (including Swedish, Greek, Hebrew and Arabic) took this word from Italian word "antico" (obsolete "antiquo") or directly from its Latin predecessor "antīquus", which originates from Proto-Indo-European *h₂énti-h₃kʷós (“appearing before, having prior aspect”).
Actually the native Greek word is αρχαίος whereas αντίκα was borrowed from Italian as you can see from this quote
αντίκα < ιταλική antica, θηλυκό του antico < λατινική antiquus < ινδοευρωπαϊκή (ρίζα) h₂énti-h₃kʷós (που έχει εμφανιστεί πιο πριν) < h₂énti (<h₂ent-: μπροστά) + h₃ekʷ- (μάτι, βλέπω)
The meaning is the same, but the phrasing is different. In Duolingo it is usually best to go with the closest natural sounding English sentence to the given Italian one. Since "The question is ancient." is both natural and as close as could be to the Italian, it is the preferred translation here.