Question: Which office holder's military unit is USS Kittiwake  and constituency is Castro District, San Francisco ?
SPARQL:
SELECT DISTINCT ?uri WHERE {?uri <http://dbpedia.org/ontology/militaryUnit> <http://dbpedia.org/resource/USS_Kittiwake_(ASR-13)> . ?uri <http://dbpedia.org/property/constituency> <http://dbpedia.org/resource/Castro_District,_San_Francisco>  . ?uri <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/OfficeHolder>}