This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hospital waste and disaster management, Occupational health, Subject name: Social & Preventive Medicine
"Farmer's Lung" is due to inhalation of - 
Select and explain. 
A. Cotton fiber, B. Sugarcane fiber, C. Hay dust, D. Coal dust
C: Hay dust
Answer: C: Hay dust 
Explanation: - farmers lungs is due to the inhalation of mouldy or hay dust. - micropolyspora faeni is the main cause of farmer's lung. - repeated attacks cause pulmonary fibrosis, inevitable pulmonary damage and cor pulmonale. Reference: Park's textbook of preventive and social medicine, 23rd edition, pg no:807 <\p>