What what is Christian Church office held by head of the organisation pope and which that starts with c
SELECT DISTINCT ?sbj ?sbj_label WHERE { ?sbj wdt:P31 wd:Q34651 . ?sbj wdt:P2388 wd:Q19546 . ?sbj rdfs:label ?sbj_label . FILTER(STRSTARTS(lcase(?sbj_label), 'c')) . FILTER (lang(?sbj_label) = 'en') } LIMIT 25 
christian church: Q34651 pope: Q19546