This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
A 45 year old female patient presents with symptoms of easy bruisabilty and frequent headaches. Physical examination shows moderate splenomegaly. Blood counts show a normal leucocyte count and platelet count of 1000 × 103/cu mm. The leukocyte alkaline phosphatase score is normal. Which of the following is the drug of choice for the treatment of this patient? 
Select and explain. 
A. Hydroxy urea, B. Radioactive phosphorous, C. Anagrelide, D. Interferon alpha
A: Hydroxy urea
Answer: A: Hydroxy urea 
Explanation: None