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
Serum sickness syndrome is: 
Select and explain. 
A. A transplant immunity, B. An anaphylactic shock, C. Systemic arthus reaction, D. None of the above
C: Systemic arthus reaction
Answer: C: Systemic arthus reaction 
Explanation: None