Final answer:
The real threat to expunging polyphony at the Council of Trent was the concern that it might obscure the clarity of church service texts and was considered at odds with the religious reforms of simplicity.
Step-by-step explanation:
The only real, serious threat to expunging polyphony at the Council of Trent concerned the belief that complex musical forms could obscure the clarity of the liturgical text, possibly leading to misunderstandings of the words of the church service. This was a period of religious reform, and clarity in services was seen as essential to counteract the Protestant Reformation. Some even considered polyphony to be frivolous or opulent, which clashed with the calls for a return to simplicity and spirituality in church practices.