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: Medicine
45 yr old on Mtx develops respiratory symptoms? 
Select and explain. 
A. Bacterial pneumonia, B. TB due to drug therapy, C. Nonspecific interstitial pneumonia, D. Nonspecific interstitial pneumonia
C: Nonspecific interstitial pneumonia
Answer: C: Nonspecific interstitial pneumonia 
Explanation: Ref - Harrisons internal medicine 20e