Materials involved in a "Class A" fire include ordinary combustible materials such as _______ and _______.

In the context of fire classification, a "Class A" fire pertains to those that involve ordinary combustible materials. This class specifically includes materials such as paper and wood, which are considered common fuel sources that ignite and burn easily. These types of fires are typically extinguished with water, as the heat from these materials allows for effective cooling and suppression.

Class A fires are characterized by the burning of everyday items and organic materials, which are abundant in residential and commercial environments. This distinction is essential for understanding fire safety protocols, firefighting techniques, and the type of extinguishing agents that are most effective for each class of fire.

The other choices describe materials that fall under different fire classifications. For example, gasoline and oil are flammable liquids classified as Class B fires, while plastics and rubber are also involved in other fire classes that may require different suppression methods. Understanding these classifications is crucial for effective fire response and safety measures.