The following are multiple choice questions (with answers) about medical knowledge.   **Question:** Anaphylaxis is mediated by   (A) 5-hydroxytryptamine   (B) Heparin   (C) ProstaglandinImmunology   (D) All of these
['(D) All of these <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) 5-hydroxytryptamine \n (B) Heparin \n (C) ProstaglandinImmunology \n (D) All of these <> possible answers', '  Anaphylaxis is mediated by <> context@']