A fire extinguisher that is identified with a square can be used to put out which fire?

The identification of a fire extinguisher with a square typically indicates that it is a Class B extinguisher, which is designed to extinguish fires involving flammable liquids such as gasoline, oil, and other similar substances. Class B extinguishers contain agents that can effectively combat fires caused by these types of materials, which can ignite and create dangerous situations.

In the context of the choices provided, the correct answer, the fire extinguisher can indeed be used for oil fires, aligning with the properties of a Class B extinguisher. Options involving wood and electrical fires fall under different classes; for example, wood fires are usually tackled with Class A extinguishers, while electrical fires require Class C extinguishers, specifically designed to handle the unique hazards presented by electrical equipment. Understanding these classifications is crucial for selecting the appropriate extinguisher for different types of fire incidents.