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
[{'content': 'Serum sickness is: \nSelect and explain. \nA. Type 1 hypersensitivity reaction, B. Type 2 hypersensitivity reaction, C. Type 3 hypersensitivity reaction, D. Type 4 hypersensitivity reaction', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans: C. Type 3 hypersensitivity reaction(Ref: Robbins 9/e p207)Serum sickness is the prototype of a systemic immune complex disease or type III hypersensitivity reaction.Immune Complex--Mediated (Type III) Hypersensitivity:Acute serum sickness is the prototype of a systemic immune complex disease; it was once a frequent sequela to the administration of large amounts of foreign serum (e.g., serum from immunized horses used for protection against diphtheria).', 'role': 'assistant'}]