Which class of fire includes combustible solids such as wood and paper?

The correct answer is Class A, as this class specifically encompasses fires that involve combustible solids, which includes materials such as wood, paper, cloth, rubber, and certain kinds of plastics. Class A fires are typically characterized by their ability to leave ash after burning, hence the name "Class A."

Understanding the classification of fires is crucial for effective fire management and safety measures. Class A fire extinguishers are typically filled with substances like water or foam, which can cool the burning material and help to extinguish the flames effectively.

In comparison, Class B fires involve flammable liquids or gases like gasoline, oil, or paints, and require extinguishers that can smother the flames, such as foam or dry chemical agents. Class C fires involve electrical equipment and require non-conductive extinguishing agents. Class D fires are specific to combustible metals, such as magnesium or sodium, and require specialized extinguishing methods suitable for such materials.