Question: The tune of "O Sanctissima" has been notably reused in the first half of a American civil rights anthem that is most commonly attributed as having descended lyrically from what hymn?
Sentence (from "Septima Poinsette Clark"): Septima Poinsette Clark (May 3, 1898 – December 15, 1987) was an American educator and civil rights activist.
Relevant evidence: No