Article: Music was an important part of both secular and spiritual culture, and in the universities it made up part of the quadrivium of the liberal arts. From the early 13th century, the dominant sacred musical form had been the motet; a composition with text in several parts. From the 1330s and onwards, emerged the polyphonic style, which was a more complex fusion of independent voices. Polyphony had been common in the secular music of the Provencal troubadours. Many of these had fallen victim to the 13th-century Albigensian Crusade, but their influence reached the papal court at Avignon.

Now answer this question: What was the dominant sacred musical form in the early 13th century?
the motet