Final answer:
Sir Gawain is nicked by the Green Knight but forgiven, leading him to wear a green belt as a symbol of humility. He is honored at Camelot, where other knights choose to wear green belts in solidarity.
Step-by-step explanation:
The statement refers to the story of Sir Gawain and the Green Knight, a narrative central to Arthurian legends. Gawain, indeed, receives only a nick on his neck as a result of his honesty. He is forgiven by the Green Knight, who is actually the lord of the castle where Gawain had been staying. Gawain wears the green belt as a reminder of both his humility and the lesson in honesty and integrity he learned during his quest. Upon returning to Camelot, he is welcomed by King Arthur and his knights of the Round Table, who honor Gawain's experience by deciding to wear green sashes themselves. Hence, the statement in question is true.