Final answer:
The carpal bone that is demonstrated distal and lateral to the lunate in the PA oblique projection of the wrist is the triquetrum.
Step-by-step explanation:
In the PA oblique projection of the wrist, the carpal bone demonstrated distal and lateral to the lunate is the triquetrum. The triquetrum is the third of the four proximal carpal bones and on the lateral side, it articulates with the lunate laterally, the hamate distally, and has a facet for the pisiform. When using the mnemonic 'So Long To Pinky, Here Comes The Thumb,' which helps to remember the carpal bone arrangement from lateral to medial in both rows starting with the proximal, the triquetrum is indicated before the pisiform and is followed medially by the hamate in the distal row. The trapezium and trapezoid are also distal carpal bones, but they are located more lateral than the triquetrum and are not the bones that are found distal and lateral to the lunate in the specified X-ray view.