This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Lung, Subject name: Surgery
Bronchiolithiasis means 
Select and explain. 
A. Calcified lymph nodes eroding into bronchus, B. Foreign body calcified in bronchus, C. Lithium deposition in bronchial wall, D. A hamartoma
A: Calcified lymph nodes eroding into bronchus
Answer: A: Calcified lymph nodes eroding into bronchus 
Explanation: Ans: a (Calcified lymph nodes eroding into bronchus)Ref: Dorland's 28thed, p. 231