This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Haematology, Subject name: Anatomy
Which of these is the most impoant prognostic factor in ALL? 
Select and explain. 
A. Hyperploidy, B. Total leucocyte count greater than 50,000, C. Age, D. Response to steroids
D: Response to steroids
Answer: D: Response to steroids 
Explanation: Responds to steroids is the most consistent marker in the patients of ALL. (ref Robbins 9th/590-593)