Final answer:
The strategy EMS agencies use for arranging ambulances to reduce response times is known as deployment.
Step-by-step explanation:
The strategy used by an EMS (Emergency Medical Services) agency to maneuver its ambulances and crews in order to reduce response times is known as deployment. This strategic positioning of resources is crucial for ensuring that emergency medical help arrives as quickly as possible. Deployment involves placing ambulances and personnel in locations where they are most likely needed, based on factors like historical call data, time of day, special events, and anticipated demand. This is different from maintenance which relates to the upkeep of the vehicles to ensure they are in safe and working condition, as outlined in the historical context provided by Grace's observation in her diary. Efficient deployment can significantly impact an agency's ability to provide prompt and effective emergency medical services to the community.