<prompt> A 23 years old asymptomatic female has MCV-70fl, ferritin - 100gL, Hb-10gm. Which of the following is the most likely cause?B12 deficiencyIron deficiencyFolate deficiencyThalassemia trait  <response>: This patient presenting with mild degree of microcytic anemia MCV70 with normal ferritin levels 100pgL suggesting a diagnosis of thalassemia trait. Patients with beta thalassemia trait often presents as mild microcytic hypochromic anemia with target cells. Their mean corpuscular volume is rarely 75 fL and the hematocrit is rarely . Ref: Wintrobes Atlas of Clinical Hematology By Douglas. C. Tkachuk, Jan.V.Hirschmann, Page 14; Harrisons Principles of Internal Medicine, 18th Edition, Chapters 104-105; CURRENT Medical Diagnosis and Treatment, 2012, Chapter 13 