<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 47-year-old woman comes to the physician because of easy bruising and fatigue. She appears pale. Her temperature is 38C 100.4F. Examination shows a palm-sized hematoma on her left leg. Abdominal examination shows an enlarged liver and spleen. Her hemoglobin concentration is 9.5 gdL, leukocyte count is 12,300mm3, platelet count is 55,000mm3, and fibrinogen concentration is 120 mgdL N 150400. Cytogenetic analysis of leukocytes shows a reciprocal translocation of chromosomes 15 and 17. Which of the following is the most appropriate treatment for this patient at this time?? A: Platelet transfusion, B: Rituximab, C: All-trans retinoic acid, D: Imatinib, E: Cyclophosphamide,  <response>: This is a clinical vignette describing a patient with easy bruising, fatigue, pallor, fever, enlarged liver and spleen, low hemoglobin, thrombocytopenia, leukocytosis, and abnormal fibrinogen levels. Cytogenetic analysis shows a translocation between chromosomes 15 and 17, which is characteristic of acute promyelocytic leukemia APL. The clinical presentation and cytogenetic findings are most consistent with APL. The goal of treatment in APL is to induce remission and prevent life-threatening bleeding by correcting the coagulopathy. All-trans retinoic acid ATRA is the treatment of choice for APL as it drives abnormal promyelocytes to differentiate into mature granulocytes, correcting the coagulopathy.Platelet transfusion may help temporarily control bleeding but does not treat the underlying APL. Rituximab is used for B cell lymphomas, not APL. Imatinib is used for chronic myeloid leukemia with the Philadelphia chromosome translocation, not APL. Cyclophosphamide is a chemotherapy agent that would not be appropriate as initial therapy for newly diagnosed APL.C: All-trans retinoic acid 