This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiration, Subject name: Pathology
Which cells produce surfactant in conducting part of the lung? 
Select and explain. 
A. Goblet cells, B. Brush cells, C. Basal cells, D. Clara cells
D: Clara cells
Answer: D: Clara cells 
Explanation: Ans. (d) Clara cells(Ref: Robbins 9th/pg 670; 8th/pg 679)Club cells, also known as bronchiolar exocrine cells, originally known as Clara cells, are dome-shaped cells with short microvilli, found in the small airways (bronchioles) of the lungs, produce substances similar to surfactant.