Organum is:
B. A style of early polyphony.
In music, organum refers to a form of early polyphony where voices sing in parallel intervals, typically at a fixed interval such as a perfect fourth or a perfect fifth above or below the main melody. Organum was commonly used in medieval Western music to enhance the beauty and complexity of sacred vocal compositions.
This style of composition allowed for the creation of harmonies through the addition of one or more voices singing different notes simultaneously with the original melody. Organum played a significant role in the development of Western classical music and provided a foundation for more intricate forms of polyphony that emerged in later musical periods.
