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: Pathology
[{'content': 'Intrinsic cell wall defect of RBCs is feature of - \nSelect and explain. \nA. Paroxysmal nocturnal hemoglobinuria, B. Sickle cell anemia, C. Hemophilia, D. All of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Paroxysmal nocturnal hemoglobinuria is a disease that results from acquired mutations in the phosphatidylinositol glycan complementation group A gene (PIGA), an enzyme that is essential for the synthesis of ceain membrane associated complement regulatory proteins. Ref :Robbins pathologic basis of disease ; south east asia edition ;pg:642', 'role': 'assistant'}]