Final answer:
The composer referred to in the selection is most likely Hildegard von Bingen, as the other options are associated with different contributions to music rather than composing.
Step-by-step explanation:
The composer mentioned in the provided selection is most likely Hildegard von Bingen because the other figures (Johannes Gutenberg, Pope Gregory the Great, and Jacob Obrecht) were known for other contributions rather than composing a specific selection of music. Johannes Gutenberg, for example, was an inventor and publisher who notably developed the movable type printing press in Europe, revolutionizing the production of books and spreading knowledge, a key factor in the emergence of the Renaissance and the Reformation.
This invention greatly affected the distribution of music and musical theory, as described, but Gutenberg himself was not a composer. Pope Gregory the Great is often associated with the codification of the Gregorian Chant, but he did not personally compose music. Jacob Obrecht was a later composer of the Renaissance, while Hildegard von Bingen was a medieval composer known for her musical and spiritual works. Therefore, based on the information given, Hildegard von Bingen is the most likely answer.