Black and white: how many details can you see?

Classical radiology is based in the contrast between black (air) and white (soft tissue) and is still a valuable tool for diagnosis but the observation must be systematic. How many abnormalities you see in the next X-ray?
A: 1 B:2 C:3 D:0
SOLUTION: 2. Pneumotorax (right superior sulcus) and subcutaneous air