Question: Who was the father of Queen Elizabeth II?
SPARQL query:
PREFIX res: <http://dbpedia.org/resource/>
PREFIX prop: <http://dbpedia.org/property/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
SELECT DISTINCT ?uri ?string WHERE { 
        res:Elizabeth_II prop:father ?uri .
        OPTIONAL { ?uri rdfs:label ?string. FILTER (lang(?string) = 'en') }
}