Israel lists Arabic as an official language, and if you should probably include the Palestinian Territories, but if you don't want to do that, then you should at least include Israel to account for the Arab population.
This is outdated information - even when you wrote this. Arabic WAS an official language of Israel for over 70 years, but was delisted as such in July 2018. As this is a quiz based on official languages, it is correct that it is left off.