Which type of hypersensitivity reaction is responsible for anaphylaxis?
Type I hypersensitivity reactions, mediated by IgE, lead to anaphylaxis, which is a severe allergic reaction. This follows from NCERT principle where relation explains outcome clearly for students.
Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.