Final answer:
Morgan le Fey made the Green Knight green as a symbol of nature, the supernatural, and rebirth, highlighting his otherworldly nature and the themes of the challenges faced by Gawain.
Step-by-step explanation:
In Sir Gawain and the Green Knight, Morgan le Fey made the Green Knight green as a symbol with numerous interpretations. One of the prevalent interpretations is that the green color represents a connection to nature and the supernatural, setting the Green Knight apart from the mortal characters and giving a visual cue of his enchantment and otherworldliness. Additionally, green can be seen as a symbol of rebirth and regeneration, which ties into the Green Knight's ability to recover from Gawain's strike, ultimately revealing the tests and trials Gawain faces.