This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hypersensitivity Reactions: Immune-Mediated Injury, Subject name: Pathology
Anaphylactic shock is caused by w hich type of hypersensitivity reaction? 
Select and explain. 
A. I, B. II, C. III, D. IV
A: I
Answer: A: I 
Explanation: Ans. is 'a' i.e., IAnaphylactic shock is caused by type 1 Hypersensitivity reaction.