Final answer:
The nurse should caution the client against swimming until the incision has healed to avoid infection and ensure proper healing. Swimming can be a part of the rehab plan, but only with the healthcare provider's consent. Therefore, the correct option is C.
Step-by-step explanation:
A nurse's appropriate response to a client planning to go swimming after a total hip replacement would be: Explain that the incision should not be immersed in water until it has healed. It is crucial to prevent the risk of infection and to ensure that the healing process is not compromised. Swimming and engaging in range of motion exercises could be beneficial once the incision has adequately healed and with approval from the healthcare provider in charge of the appropriate physical therapy plan.