<prompt> A previously well 53-year-old man develops progressive shortness of breath. Pulmonary function tests reveal a restrictive defect and a high-resolution CT suggests pulmonary fibrosis. Which of the following is the most likely role of transbronchial biopsy in this condition?assess disease severityassess possible bronchiolar narrowingdiagnose specific causes of interstitial lung diseasedetermine degree of inflammation  <response>: Transbronchial biopsy helps differentiate idiopathic pulmonary fibrosis IPF from similar syndromes with specific treatments. These include chronic hypersensitivity pneumonitis, cryptogenic organizing pneumonia, and sarcoidosis. 