<prompt> Which of the following is the commonest cause of farmers lung?Micropolyspora faeniThermoactinomyces sacchariMycobacterium bovisNone of the above  <response>: Farmers lung is caused due to inhalation of mouldy hay or grain. Thermophillic actinomyeces, commonly Micropolyspora faeni is the common cause of farmers lung. Ref: Park 21st edition, page 748. Chapter: Occupational health. 