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: Pediatrics
Most common malignant tumour in childhood ? 
Select and explain. 
A. Rhabdomyosarcoma, B. Leukemia, C. Lymphangioma, D. Neuroblastoma
B: Leukemia
Answer: B: Leukemia 
Explanation: Ans. is 'b' i.e., Leukaemia