Problem: A 75 year old man with RA complains of pain and fatigue. Lab results are as follows: WBC 6.8 x 103 /uL RBC 3.5 x 1012 /L Hgb 9.7 g/dL Hct 29% MCV 83 fL MCHC 33.9 g/dL Serum iron - decreased TIBC - decreased Serum ferritin- sl.elevated These results are most characteristic of A. Beta-thalassemia minor B. Iron deficiency C. Sideroblastic anemia D. Anemia of chronic disease