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: Medicine
[{'content': 'A 40 year old male patient is hospitalised with huge splenomegaly, marked sternal tenderness, and a total leucocyte count of 85,000 per cubic millimetre with large percentage of myelocytes and meta myelocytes, which one of the following drugs is best indicated for his disease ? \nSelect and explain. \nA. Cyclophosphamide, B. Chlorambucil, C. Melphation, D. Hydroxyurea', 'role': 'user'}, {'content': "Answer: D \nExplanation: Chronic phase of CML begins as a proliferative disorder & consists of excessive proliferation of myeloid cells of intermediate grade(myelocytes & metamyelocytes) & mature segmented neutrophils.Drugs used in chronic phase of CML include imatinib,dasatinib, nilotinib, or classical cytotoxic drugs such as hydroxycarbamide(hydroxyurea) or interferon. Reference:Davidson's principles & practice of medicine 22nd edition pg no 1039.", 'role': 'assistant'}]