Which of the following are considered high bone marrow dose examinations?

High bone marrow dose examinations typically involve procedures that expose sensitive tissues, such as bone marrow, to increased levels of ionizing radiation. In this context, all the mentioned examinations—lumbar spine (L/S) imaging, retrograde urography, and abdominal angiography—are known to deliver significant doses of radiation due to their inherent techniques and the areas they target.

Lumbar spine imaging often requires multiple views and possibly additional imaging modalities, which can contribute to higher radiation exposure in that region. Retrograde urography involves fluoroscopy and typically uses contrast media, which can lead to prolonged exposure times and higher doses. Abdominal angiography also employs fluoroscopic guidance and the administration of contrast materials, generally resulting in substantial radiation exposure to the bone marrow.

By acknowledging that each of these examinations can contribute to significant doses, particularly to the bone marrow, it becomes clear that they all fall under the classification of high bone marrow dose examinations. Thus, the option that states "All of the above" is the most encompassing and accurately reflects the potential radiation impact of these procedures.