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: Pathology
[{'content': 'In which of the following condition PAS test has block positivity \nSelect and explain. \nA. ALL L1, B. AML, C. CML, D. Hodgkins lymphoma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Periodic acid - schiff (PAS) stain is useful for the diagnosis of ALLs and erythroid and megakoryocytic (M6 and M7) type of acute myeloid leukemia.\nBlock positivity in lymphoblast is oberved in ALL L1 cores.', 'role': 'assistant'}]