Which of the following is considered a local agency?

The Building and Safety Department is considered a local agency because it operates at the municipal or county level, providing essential services related to construction and safety regulations within specific local jurisdictions. These departments are responsible for enforcing building codes, issuing permits, and ensuring compliance with safety standards, which are integral to local governance and community safety.

In contrast, the Environmental Health Department, while potentially local in its operations, can also exist at the county level and may have broader state oversight. The California Coastal Commission serves a more regional function, focusing on the protection of coastal resources and land use planning along California's coastline, while the Air Quality Management District typically operates on a regional level, dealing with air quality issues across multiple jurisdictions rather than being limited to a single local municipality. Thus, the Building and Safety Department distinctly exemplifies a local agency's direct role in managing local building and safety regulations, setting it apart from the other options.