Which category of assessment indicates complete elimination of a threat?

The category of assessment that indicates complete elimination of a threat is "destroyed." When a threat is described as destroyed, it means that it has been entirely removed or rendered inert, meaning there is no longer a danger or risk associated with that threat. This level of assessment denotes that not only has the threat been addressed, but it has also been eradicated completely to a point where it can no longer pose any risk.

The other options represent varying levels of threat management. For instance, neutralized refers to a situation where the threat is no longer operational but may still exist in some form. Suppressed typically means that the threat is reduced in effect or visibility but is not fully eliminated. Mitigated implies lowering the severity or impact of the threat, rather than fully eliminating it. Thus, while these terms demonstrate progress in addressing a threat, they do not convey the complete eradication that "destroyed" does.