This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Childhood Tumors, Subject name: Pediatrics
Most common malignant tumour in childhood: 
Select and explain. 
A. Rhabdomyosarcoma, B. Leukaemia, C. Lymphangioma, D. Neuroblastoma
B: Leukaemia
Answer: B: Leukaemia 
Explanation: (Leukemia) (561-G) (580 -Ghai 7th)* Leukemia is most common form of childhood malignancy* Descending order - Leukemia > Brain tumour > Lymphoma > Neuroblastoma > Wilm's tumour > Soft tissue sarcoma.* Most common cancer in children (1686-Nelson 17th)* Lymphohematopoietic (44%) > Nervous system (29%) > Embryoral (12%0 > Connective tissue (10%)