One of the legacies of 20th-century music is to have blurred the definition of music as (5) ______ before.Đoạn văn23/33One of the legacies of 20th-century music is to have blurred the definition of music as (5) ______ before.not seldom ever neverGiải thíchĐáp án C Giải thích: ever before: từng có trước đây