Final answer:
The Green Knight's supernatural survival and response to Gawain's beheading of him highlight the prevalence of supernatural elements in medieval literature, distinguishing it from other literary elements such as chivalry, courtly love, and foreshadowing.
Step-by-step explanation:
The medieval literary element evident in the Green Knight's response to Gawain's hit is B. Supernatural elements. The story "Sir Gawain and the Green Knight" features the encounter between Gawain, a knight of King Arthur's court, and the mysterious Green Knight. After Gawain beheads the Green Knight, the Green Knight picks up his own head and speaks, setting a challenge for Gawain to meet him one year later. This act goes beyond the natural and demonstrates the incorporation of the supernatural within medieval literature, a common trope designed to challenge the protagonist and often to test his virtues.
Chivalry refers to the code of conduct that knights were expected to follow, which not only included martial prowess but also virtues like bravery, courtesy, honor, and gallantry towards women. Courtly love is a recurring theme in medieval literature where knights express romantic affection in a highly idealized and often ritualistic manner. Foreshadowing serves as a device used to hint at future events in a story.