What is the {human} for {production company} of {The Birth of a Nation}
Who made the B of N?
Who produced The Birth of a Nation?
SELECT DISTINCT ?o WHERE { resource:The_Birth_of_a_Nation property:production_company ?o . ?o rdf:type ontology:human }
select distinct ?obj where { ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q220394> . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P272> . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj . ?obj <http://www.wikidata.org/entity/P31> <http://wikidata.dbpedia.org/resource/Q5> } 
 select distinct ?obj where { wd:Q220394 wdt:P272 ?obj . ?obj wdt:P31 wd:Q5 } 