Which of these anemias is hypochromic and microcytic?

Hypochromic and microcytic anemias are characterized by red blood cells that are smaller than normal (microcytic) and have less hemoglobin, which causes a paler appearance (hypochromic). Thalassemia is a classic example of this type of anemia because it results from an inherited defect in hemoglobin synthesis, leading to reduced production of one of the globin chains. This deficiency affects the formation of hemoglobin within the red blood cells, making them smaller and less pigmented.

Macrocytic anemia, resulting from deficiencies such as vitamin B12 or folate deficiency, shows larger than normal red blood cells, thus does not fit the hypochromic and microcytic classification. Aplastic anemia is characterized by a deficiency of all blood cell types due to failure of bone marrow function, and sickle cell anemia leads to abnormal shape rather than size or hemoglobin content reductions. Therefore, thalassemia stands out as the only condition that specifically exhibits both hypochromic and microcytic properties in its anemic presentation.