Which of the following is a characteristic of leukemia?

The characteristic of leukemia is the overproduction of immature white blood cells. In leukemia, the bone marrow produces large numbers of abnormal leukocytes, which are not fully developed and therefore cannot perform their immune function effectively. This accumulation of immature white blood cells disrupts the normal production of other blood cells, including red blood cells and platelets, often leading to symptoms such as anemia and thrombocytopenia.

Additionally, healthy red blood cell production is typically decreased, not increased, in leukemia due to the overcrowding of the marrow. The overproduction of platelets may occur in certain conditions, but leukemia usually presents with lower platelet levels or coagulopathy due to the ineffective functioning of blood cells. While leukemia can sometimes be asymptomatic in early stages, it usually presents with various symptoms, including fatigue, frequent infections, and easy bruising or bleeding as the disease progresses. Thus, the overproduction of immature white blood cells is a defining characteristic of leukemia.