Which of the following is one of the three groups that the EPA uses to categorize ACM?

The correct answer highlights one of the specific categories that the Environmental Protection Agency (EPA) uses to classify Asbestos Containing Materials (ACM). Insulation on boilers, pipes, ducts, tanks, and other equipment is recognized as a significant category because it pertains to materials that are commonly found in various industrial and commercial settings. These types of insulation are often at a higher risk for disturbance during maintenance activities, and thus, they require strict adherence to safety protocols and regulations due to the potential for asbestos exposure.

The other choices mention types of materials or contexts where asbestos may be found but do not align with the EPA's specific categorization criteria. Residential insulation, insulation in schools, and fireproofing materials may all contain asbestos, but they do not represent the distinct categories recognized by the EPA in their official assessments of ACM. Understanding these classifications is crucial for compliance with regulations and for ensuring the safety of workers and the public regarding asbestos exposure.