This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous system, Subject name: Physiology
Macrophage is CNS 
Select and explain. 
A. Fibrous Astrocyte, B. Microglia, C. Oligodendrocyte, D. Protoplasmic astrocyte
B: Microglia
Answer: B: Microglia 
Explanation: Microglia are scavenger cells in CNS that resemble tissue macrophages and remove debris resulting from the injury. Ganong's review of medical physiology; 23rd edition; pg: 80