Final answer:
An example of a protective action from the provided choices is A. evacuation, which is crucial during a radioactive material emergency to protect public health.
Step-by-step explanation:
An example of a protective action is A. evacuation. This is a measure taken to ensure the safety of people in the event of a situation such as the release of radioactive material. As referenced, an evacuation zone is established around areas that have received heavy doses of radioactive fallout. This helps to protect the public from harmful exposure to radiation. Evacuation is a direct action taken to safeguard human health in response to an emergency, whereas the other options are preparatory or supplementary actions supporting a protective action or overall safety plan.