A client has just begun treatment with busulfan, 4 mg by mouth daily, for chronic myelogenous leukemia. The client receives busulfan until their white blood cell (WBC) count falls to between 10,000/mm3 and 25,000/mm3. Then the drug is stopped. When should treatment resume?A. When the WBC count rises to 50,000/mm3B. When the client displays anemiaC. When last hair begins to grow backD. When the WBC count falls to 50,000/mm3