Final answer:
The nursing student should explain that nurses should not have social contact with patients outside of professional boundaries and offer to answer any additional questions before the patient's discharge, thus maintaining medical professionalism and ethics.
Step-by-step explanation:
In response to the patient's request, the nursing student should choose option c: Explain that nurses are not permitted to have social contact with patients but offer to answer questions before the patient is discharged. This response adheres to professional boundaries and nursing ethics, which typically discourage personal relationships with patients that may compromise professional judgment or patient care. Even though social media can be an easy way to stay in touch and share information, it is important to maintain professionalism and the integrity of the nurse-patient relationship.