Which of the following is considered an accelerant?

An accelerant is a substance that is used to facilitate the spread of fire or to make it burn more easily. Gasoline is a classic example of an accelerant due to its high volatility and ability to ignite quickly. When gasoline is poured onto a material, it vaporizes, creating an explosive atmosphere that can significantly increase the intensity and speed of a fire. This property is what makes it a commonly used accelerant in arson cases.

In contrast, wood serves as a combustible material rather than an accelerant, as it requires a sustained heat source to ignite, but does not enhance the spread of flames on its own. Water is primarily used as a fire suppressant; it cools burning materials and reduces the oxygen available for combustion. Concrete is non-combustible and is used as a building material, providing no assistance in the ignition or spreading of fire. Thus, gasoline is definitively categorized as an accelerant due to its unique chemical properties that aid in igniting and fueling a fire.