Final answer:
The correct subject is Health. Full building evacuation is the normal course of action for situations with uncertainty over a serious fire or hazard after an alarm and potential extreme physical danger.
Step-by-step explanation:
The correct subject for the question is Health.
In the context of the question, full building evacuation is the normal course of action for situations that involve uncertainty over whether a serious fire or hazard awaits after an alarm and the potential for extreme physical danger.
For example, full building evacuation is commonly seen in situations such as a fire alarm going off in a school or workplace, where there is uncertainty about the extent of the fire and the potential danger it poses to occupants.