Final answer:
The lyrics of the motet "Quam pulchra es" come from the Bible. It is believed that the lyrics were inspired by a passage in the Song of Solomon, chapter 4 verse 1, which is a love poem between the bride and the bridegroom.
Step-by-step explanation:
The lyrics of the motet "Quam pulchra es" come from A. The Bible. In the Bible, there is a passage in the Song of Solomon, specifically chapter 4 verse 1, that begins with the words "quam pulchra es" which means "how beautiful you are" in Latin.
This passage is a love poem between the bride and the bridegroom, and it is believed that the lyrics of the motet were inspired by this biblical text.