<s>[INST] context: Acute lymphoblastic leukemia, also known as acute lymphocytic leukemia or acute lymphoid leukemia (ALL), is an acute form of leukemia, or cancer of the white blood cells, characterized by the overproduction and accumulation of cancerous, immature white blood cells, known as lymphoblasts. In persons with ALL, lymphoblasts are overproduced in the bone marrow and continuously multiply, causing damage and death by inhibiting the production of normal cells (such as red and white blood cells and platelets) in the bone marrow and by spreading (infiltrating) to other organs. ALL is most common in childhood, with a peak incidence at 2-5 years of age and another peak in old age.The most common causes of splenomegaly in developed countries are infectious mononucleosis, splenic infiltration with cancer cells from a hematological malignancy and poal hypeension (most commonly secondary to liver disease, and Sarcoidosis). Splenomegaly may also come from bacterial infections, such as syphilis or an infection of the hea's inner lining (endocarditis)The causes of massive splenomegaly (spleen >1000 g) are fewer, and include: visceral leishmaniasis (kala-azar) chronic myelogenous leukemia myelofibrosis malaria splenic marginal zone lymphoma [/INST] question: Massive splenomegaly is not a feature of- | options: A: Acute lymphocytic leukemia B: Chronic myeloid leukemia C: Myelofibrosis with myeloid metaplasia D: Hairy cell leukemia | answer: A </s>