A 45 year old female patient presents with symptoms of easy bruisability and frequent headaches. Physical examination show a moderate splenomegaly. Blood counts shows a normal leucocyte count and a platelet count of 1000 × 103/ cu mm. The leucocyte alkaline phosphatase score is normal. Which one of the following is the drug of choice for the treatment of this patient?a) Hydroxyureab) Radioactive phosphorusc) Anagrelided) Interferon alpha