Question

to ensure that an anteroposterior (ap) mobile chest radiograph is free of rotation, what structures should appear symmetrical?
ribs and clavicles
scapulae and humeri
sternum and xiphoid process
lung apices and costophrenic angles

Explanation:

In an AP mobile chest radiograph, to check for lack of rotation, the ribs and clavicles should appear symmetrical. The ribs and clavicles are bilateral structures that provide a clear indication of proper positioning. Asymmetry in these structures suggests rotation of the chest during imaging.

Answer:

Ribs and clavicles