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
Arsenic is used in treatment of: 
Select and explain. 
A. Acute promyelocytic leukemia, B. A.L.L, C. CML, D. Transient myeloproliferative disorder
A: Acute promyelocytic leukemia
Answer: A: Acute promyelocytic leukemia 
Explanation: Answer is A (Acute promyelocytic leukemia)