Giovanni Palestrina was an excellent organist, but performed in choirs.

Palestrina's Missa Papae Marcelli conformed to the Council of Trent's requirements by emphasizing clarity of text through a controlled use of polyphony and avoiding excessive ornamentation in the music. The text could be clearly heard and understood, reflecting the Council's desire for sacred music to enhance the worship experience without overshadowing the liturgical text.

That would be Renaissance music. Specifically, Palestrina was a pioneer of the "Counter-Point" style of polyphonic choir music in the mid 1500's Italian Renaissance. Please correct me if I'm wrong, I've only sung his music in church choir, I have not studied it.

Palestrina's Missa Papae Marcellus adhered to the Council of Trent's requirements by featuring clear text setting, intelligible polyphony, and avoiding excessive ornamentation or complex musical gestures that could obscure the sacred text. The work aimed to enhance the clarity and solemnity of the liturgical text, reflecting the council's desire for music that would aid in the faithful's understanding and devotion during the Mass.