A client with persistent low back pain has received a prescription for an electronic stimulator (TENS) unit. After the nurse applies the electrodes and turns on the power, the client reports feeling a tingling sensation. How should the nurse respond?

A) Incorrect - Skin redness might indicate irritation, but the initial focus should be on the client's sensation. B) Incorrect - Decreasing the strength of the electrical signals might be premature if the sensation is normal. C) Incorrect - The amount of gel coating on the electrodes might not be the primary issue if the client is feeling a tingling sensation. D) Correct- A tingling sensation is normal and expected when using a TENS unit, and it does not indicate any harm or damage to the skin or nerves. However, the sensation should not be painful or unpleasant for the client, and the nurse should adjust the intensity of the electrical signals accordingly.