A 30 yr. old female, case of anemia, not responding to iron and folic acid B12 supplement was evaluated fuher. Her CBC profile was as follows Hb-4.7g/dl. Total WBC count -4,000/mm3 Platelet count- 70,000/mm3 Her PS finding is given below. Her Bone marrow aspirate revealed a dry tap following which a bone marrow biopsy confirmed the diagnosis. Which of the following stains would have been useful in confirming the bone marrow biopsy?