A nurse is caring for a client who has generalized petechiae and ecchymoses. The nurse should expect a prescription for which of the following laboratory tests?

A. Creatinine clearance is used to assess kidney function, not related to petechiae or ecchymoses. B. Potassium levels are important for assessing electrolyte balance but are not directly related to petechiae or ecchymoses. C. Petechiae and ecchymoses are signs of bleeding, often due to a low platelet count, so this test is appropriate. D. Prealbumin is a protein marker for nutrition, not directly related to bleeding or clotting issues.