What is {position held} of {Arthur Balfour} that is {replaces} is {Edward Grey, 1st Viscount Grey of Fallodon} ?
What position did Arthur Balfour take over from Edward Grey, 1st Viscount Grey of Fallodon?
What position did Arthur Balfour hold when he replaced Edward Grey, 1st Viscount Grey of Fallodon?
SELECT ?c WHERE { ?t property:position_held ?c . ?t property:replaces resource:Edward_Grey,_1st_Viscount_Grey_of_Fallodon . resource:Arthur_Balfour property:position_held ?t }
select distinct ?obj  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q19008> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P39> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
?statement <http://www.wikidata.org/entity/P1365> <http://wikidata.dbpedia.org/resource/Q335187>
} 

SELECT ?obj WHERE { wd:Q19008 p:P39 ?s . ?s ps:P39 ?obj . ?s pq:P1365 wd:Q335187 }