A nurse is caring for an 8-year-old client who has been diagnosed with acute rheumatic fever. Which action is the nurse's priority for a client with this presentation?

A. While reviewing the CBC is important, it is not the priority. B. Assessing joint pain is necessary for managing symptoms, but it is not the most critical initial action. C. Evaluating the erythematous rash is part of the assessment, but it does not take precedence. D. Auscultating the heart is the priority because acute rheumatic fever can lead to carditis, which can cause significant and potentially life-threatening heart complications. Early detection of abnormal heart sounds is crucial.