Final answer:
Creon worries about Medea primarily due to her foreignness and reputation for stealthy, calculated treachery, not physical manhandling. His fears are informed by her past actions involving poison and sorcery, making the correct answer 'Her foreignness'.
Step-by-step explanation:
Creon worries about Medea primarily because of her foreignness, which he associates with cunning and the capability to commit treacherous acts. Creon's concerns are not focused on physical manhandling, as Medea's actions were not of physical violence but of a cunning and calculated nature, often involving poison and sorcery, as seen when Medea sent a poisoned cloak to her ex-husband's new bride, leading to tragedy.
In addition to her foreign origins and reputation for witchcraft, Creon's fear is likely compounded by the knowledge that Medea is capable of rational yet drastic actions in her quest for revenge, as demonstrated by Euripides in his plays. His decision to banish Medea is influenced by his fear of becoming the victim of her vengeance, particularly given her resourcefulness and the dire outcomes of her previous actions.
Therefore, the correct answer to the student's question about what worries Creon about Medea would be 2) Her foreignness.