Question: Where is Arabic the official language, in the Arab world?
Answer(s):
answer: Bahrain
answer: Saudi Arabia
answer: Yemen
answer: Djibouti
answer: Jordan
answer: Libya
answer: Lebanon
answer: Mauritania
answer: Oman
answer: Qatar
answer: Sudan
answer: Syria
answer: Tunisia
answer: Iraq
answer: Algeria
answer: United Arab Emirates

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ns:m.0jzc)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
ns:m.0jzc ns:language.human_language.countries_spoken_in ?x .
?x ns:location.country.official_language ns:m.0jzc .
?x ns:location.location.containedby ns:m.0150_4 . 
}