Final answer:
No deity in Book 17 of the Iliad takes the form of a Phoenix to push the Greeks to fight over Patroclus' body. This confusion may arise from the complex ways Greek gods are known to interact with mortals in mythology. None of the options are correct.
Step-by-step explanation:
In Book 17 of the Iliad, it is not a deity that takes the form of the Phoenix but rather a mortal ally. While the gods in Greek mythology, such as Apollo and Hermes, did often intervene in the affairs of mortals, no god or goddess specifically takes the form of a Phoenix in this scene.
The confusion here may stem from a misinterpretation of the text, as the gods did frequently shapeshift and interact with humans in mythological tales. The Greek gods were known for their shifting forms as detailed in the LibreTexts accounts of Olympian gods and their frequent intervention in human affairs.
The gods listed in the traditional pantheon include deities like Zeus, Hera, Poseidon, Hades, Athena, Apollo, Artemis, and others. However, none of these gods appear as a Phoenix in this moment of the epic. None of the options are correct.