Which is the Christian denomination of the office held by head of the organisation of Pope of the Coptic Orthodox Church of Alexandria and starts with the letter a?
SELECT DISTINCT ?sbj ?sbj_label WHERE { ?sbj wdt:P31 wd:Q879146 . ?sbj wdt:P2388 wd:Q58451 . ?sbj rdfs:label ?sbj_label . FILTER(STRSTARTS(lcase(?sbj_label), 'a')) . FILTER (lang(?sbj_label) = 'en') } LIMIT 25 
christian denomination: Q879146 pope of the coptic orthodox church: Q58451