Final answer:
Method C, which involves applying the medication to the lesions with a cotton swab, is the method the nurse implements for treatment with lidocaine gel.
Step-by-step explanation:
The nurse implements method C for treatment with lidocaine gel. Method C involves the nurse applying the medication to the lesions with a cotton swab. This method allows for direct application of the medication to the specific area of concern, providing targeted relief for the client's oral lesions.