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 20 yrs adult presents with severe hypoplastic anemia. Which of the following represent the most effective treatment? 
Select and explain. 
A. IL-2, B. a - interferon, C. Anti thymocyte globulin, D. Bone marrow transplant
D: Bone marrow transplant
Answer: D: Bone marrow transplant 
Explanation: Bone marrow transplantation from matched siblings after a preparative regimen of high dose cyclophosphamide and antithymocyte globulin can cure up to 90% of patients aged less than 40 years with severe aplastic anemia. Ref: Current Medical Diagnosis and Treatment, 2012, Chapter 13; Harrison's Principle of Internal Medicine, 18th Edition, Chapter 114