Question: What city uses Persian as its official language?
Choices: Algiers
Chongqing
Iran
Catania
Cork
Indore
Tehran
Brescia
Kingston
Mashhad
SPARQL: SELECT DISTINCT ?e WHERE { ?e <pred:instance_of> ?c . ?c <pred:name> "city" . ?e <official_language> ?e_1 . ?e_1 <pred:name> "Persian" .   }
Program:
function: Find
inputs: Persian
function: Relate
dependencies: 0
inputs: official language
backward
function: FilterConcept
dependencies: 1
inputs: city
function: What
dependencies: 2
Answer: Mashhad