Which of the following best describes UXO?

The description of UXO, or Unexploded Ordnance, accurately aligns with the identification of explosives that failed to detonate upon impact. UXO refers specifically to military munitions such as bombs, shells, grenades, or other ordnance that were deployed during combat or training but did not explode as intended. These items can vary in age and are often left in the ground after conflicts or military activities, posing a potential risk to safety and requiring proper handling.

In distinguishing this from other options, munitions that have been used in conflict may have detonated successfully, thus not fitting the definition of UXO. Tools required for bomb disposal are indeed part of the safety measures surrounding UXO but do not define what UXO itself is. Lastly, while hazardous waste generated from military operations may overlap with issues related to war, it does not describe the specific nature of UXO, which is about the ordnance that remains a threat due to inoperative explosives.