This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Haematology, Subject name: Anatomy
[{'content': "Which of the following conditions is associated with microcytic hypochromic anemia \nSelect and explain. \nA. Sickle cell anemia, B. Thalassemia, C. Fanconi's anemia, D. Hereditary spherocytosis", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ref Harrison 19 th ed pg 637 Hypochromia and microcytosis characterize all forms of b thal- assemia because of the reduced amounts of hemoglobin tetramers . In heterozygotes (b thalassemia trait), this is the only abnormality seen. Anemia is minimal. In more severe homozygous states, unbalanced a- and b-globin accumulation causes accumulation of highly insoluble unpaired a chains. They form toxic inclusion bod- ies that kill developing erythroblasts in the marrow. Few of the pro- erythroblasts beginning erythroid maturation survive. The surviving RBCs bear a burden of inclusion bodies that are detected in the spleen, shoening the RBC life span and producing severe hemolytic anemia', 'role': 'assistant'}]