When an incident expands .

only the functions and positions necessary are filled.

Explanation:

The Incident Command System is an effective management tool that helps in commanding, controlling, and coordinating with the emergency responders during a time of emergency. The tool first was developed in response to the Wildfires in the forests of California and Arizona.

When an Incident Commander expands the incidents he adds positions and functions as per the requirements of the organization only. The positions that come under the expanding of an organization are command staff, general staff, etc.

So, the correct answer is that only necessary positions and functions are filled at the time of incident expansion.

answer; incorporation;