All are cavitating lesions in the lungs, except?
Caplan's syndrome
Hamaoma
Wegner's granuloma
Squamous cell carcinoma
Answer is B (Hamaoma): Hamaomas produce non cavitating popcorn calcifications. Malignant lesions (squamous cell carcinoma) and granulomatous lesions (Wegener's granulomatosis, Caplan's syndrome) are established causes of cavitatory lesions.