This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunity, Subject name: Pathology
Preformed antibodies cause: 
Select and explain. 
A. Hyperacute rejection, B. Acute rejection, C. Chronic rejection, D. Acute humoral rejection
A: Hyperacute rejection
Answer: A: Hyperacute rejection 
Explanation: Ans. (a) Hyperacute rejection(Ref: R 9th/pg 231-234)Hyperacute rejection occurs when preformed antidonor antibodies are present in the circulation of the recipient even prior to transplantation.