tell me the port city with the highest point that starts with lettter "b" in Tibidabo.
SELECT DISTINCT ?sbj ?sbj_label WHERE { ?sbj wdt:/instance of/ wd:/port settlement/ . ?sbj wdt:/highest point/ wd:/Tibidabo/ . ?sbj rdfs:label ?sbj_label . FILTER(STRSTARTS(lcase(?sbj_label), 'b')) . FILTER (lang(?sbj_label) = 'en') } LIMIT 25 