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: Medicine
Which of the following is a cause for autoimmune hemolytic anemia? 
Select and explain. 
A. CLL, B. IMN, C. Sickle cell anemia, D. Both CLL & IMN
D: Both CLL & IMN
Answer: D: Both CLL & IMN 
Explanation: In sickle cell anemia the hemolysis is due to structural defect in the B chain causing increased stickiness. It is not immune related.