This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Microbiology
Immunoglobulins are secreted by: 
Select and explain. 
A. Macrophages, B. Plasma cells, C. T-cells, D. Neutrophils
B: Plasma cells
Answer: B: Plasma cells 
Explanation: None