Final answer:
A PA projection of the patella is preferred because it results in less object-to-image distance (OID), less distortion, and less magnification of the patella, providing a more accurate representation.
Step-by-step explanation:
The question is asking why a PA projection of the patella is preferred over an AP projection. The PA projection (posteroanterior) is preferred because it results in less object-to-image distance (OID), which contributes to less distortion of the image of the patella. Furthermore, there is less magnification of the patella due to the reduced OID, which results in a more accurate representation of the patella's size and shape. So, the answer is d. All of the above.