Imatinib is used in the treatment of: (A) Chronic myelomonocytic leukemia, (B) Myelodysplastic syndrome, (C) Acute lymphoblastic leukemia, (D) Gastrointestinal stromal tumors
Answer is D. Imatinib is used in the treatment of certain types of leukemia and gastrointestinal stromal tumors (GIST). 
This medication is also used to treat dermatofibrosarcoma protuberans, a type of skin tumor. Imatinib is a biologic drug, also known as targeted therapy.