This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology, Subject name: Microbiology
The function common to neutrophils, monocyte and macrophages is: 
Select and explain. 
A. Immune response, B. Phagocytosis, C. Liberation of histamine, D. Destruction of old erythrocytes
B: Phagocytosis
Answer: B: Phagocytosis 
Explanation: Ans. is 'b' i.e., Phagocytosis (Ref: Ananthanarayan, 9th/e, p. 137and 8th/e, p. 131 - 132)* Monocytes and Macrophages originate from bone marrow and their main functions are phagocytosis and Ag presentation.