Final answer:
The nurse should notify the healthcare provider of the potential adverse effect of ringing in the ears related to high-dose aspirin therapy in the elderly client with arthritis.
Step-by-step explanation:
In this case, the client's complaint of ringing in the ears is a potential adverse effect of high-dose aspirin therapy. It is important for the nurse to recognize and address this issue. Therefore, option C) notifying the healthcare provider of this potential adverse effect is the most appropriate action for the nurse to implement.