What is {position held} of {Arthur Balfour} that is {replaces} is {Edward Grey, 1st Viscount Grey of Fallodon} ?
What position did Arthur Balfour hold when he replaced Edward Grey, 1st Viscount Grey of Fallodon?
SELECT ?obj WHERE { wd:Q19008 p:P39 ?s . ?s ps:P39 ?obj . ?s pq:P1365 wd:Q335187 }
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>
} 

What position did Arthur Balfour take over from Edward Grey, 1st Viscount Grey of Fallodon?