Where is the central ray (CR) directed for an anteroposterior (AP) axial projection (Towne method) of the skull?

The central ray (CR) is directed through the foramen magnum at a caudal angle of 30 degrees for an anteroposterior (AP) axial projection using the Towne method. This positioning is crucial as it allows for optimal visualization of the occipital bone and the foramen magnum, facilitating effective assessment of the cranial base.

In this method, the 30-degree caudal angle is specifically designed to align the CR so that it intersects the anatomical structures accurately, providing a clear image of the occipital region. The orientation is essential for properly visualizing important cranial details, which is the primary goal of the Towne projection.

Other angles or directed locations mentioned in the incorrect options do not provide the same level of anatomical detail or alignment required for this specific projection.