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
All of the following drugs are used in management of ALL Except: 
Select and explain. 
A. Methotrexate, B. All - trans retinoic acid, C. Prednisolone, D. L-Asparginase
B: All - trans retinoic acid
Answer: B: All - trans retinoic acid 
Explanation: Answer is B (All - trans-retinoic acid) All - trans- retinoic acid is used in the treatment of M3 subset (Acute Promyelocytic leukemia) of Acute Myeloid Leukemia (AML) and not in ALL