This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: AIIMS 2019, Subject name: Pathology
Basophils are activated by 
Select and explain. 
A. IL - 5, B. Neutrophils, C. Killer inhibitory peptide, D. Cell fixed Ig E
D: Cell fixed Ig E
Answer: D: Cell fixed Ig E 
Explanation: Cell fixed IgE are the activators of basophils . MAST CELL BASOPHIL Foreign antigen binds to the IgE bound to cell and leads to the activation of mast cell or basophil which leads to Type 1 hypersensitivity. IL-5 leads to activation of eosinophils.