The practical nurse (PN) enters the room of a client who underwent a mastectomy eight hours ago. The PN observes the unlicensed assistive personnel (UAP) preparing to measure the client's blood pressure using an automated blood pressure device on the client's operative side. Which action should the PN implement?

A. Ensure that the client's arm remains elevated after the blood pressure is recorded: Elevation of the operative arm is important for comfort and edema prevention, but it does not address the risk of lymphedema caused by applying a blood pressure cuff to the surgical side. B. Review the client's blood pressure as soon as the UAP records the measurement: Reviewing the reading does not prevent potential harm to the operative arm. The priority is preventing injury or complications before the measurement is taken. C. Instruct the UAP to measure the client's blood pressure on the non-operative side: Blood pressure should never be measured on the side of a mastectomy because cuff pressure can increase the risk of lymphedema and impair healing. Directing the UAP to use the non-operative arm protects the client and follows best practice guidelines. D. Advise the UAP to use a manual blood pressure cuff for a more accurate reading: Accuracy is not the issue in this situation; the priority is preventing trauma to the operative arm. Using a manual cuff on the surgical side still poses a risk.