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: Surgery
Delayed haemolytic transfusion involves all except? 
Select and explain. 
A. Positive DAT, B. Spherocytes positive, C. Haemoglobinuria, D. Reduced haemoglobin
B: Spherocytes positive
Answer: B: Spherocytes positive 
Explanation: None