This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Non Hodgkin Iymphoma, Subject name: Pathology
Which of the following is not a ourable prognostic marker in pediatric acute lymphoblastic leukemia (ALL)? 
Select and explain. 
A. Hypodiploidy, B. 2-10 years of age, C. Low WBC count, D. t(12;21)
A: Hypodiploidy
Answer: A: Hypodiploidy 
Explanation: Favourable prognostic markers in pediatric ALL include age between 2 and 10 years a low white cell count hyperdiploidy trisomy of chromosomes 4, 7, and 10 the presence of a t(12;21) Several factors are associated with a worse prognosis: age younger than 2 years, largely because of the strong association of infantile ALL with translocations involving the MLL gene presentation in adolescence or adulthood peripheral blood blast counts greater than 100,000, which probably reflects a high tumor burden.