This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Physiology
Surfactants are produced by: 
Select and explain. 
A. Type 1 pneomocytes, B. Type 2 pneumocytes, C. Smooth muscle, D. Macrophages in alveoli
B: Type 2 pneumocytes
Answer: B: Type 2 pneumocytes 
Explanation: Surfactants are produced by type 2 epithelial cells(pneumocytes) of the alveoli Ref: Guyton and Hall textbook of medical physiology 12th edition, page number 320,321