Final answer:
The hazard severity category indicated by little or no adverse impact on mission capability or unit readiness is the Negligible category on the Torino Impact Hazard Scale.
Step-by-step explanation:
The hazard severity category indicated by little or no adverse impact on mission capability or unit readiness would generally fall under the category of Negligible on the Torino Impact Hazard Scale. This category signifies that the probability of collision with a near-Earth object is extremely low and that no significant damage or disruption is expected.
Factors such as little or no severe fragmentation and/or few locations, continuing decline, and extreme fluctuation do not pose a significant threat to mission capability or unit readiness.