Which of the following is an example of a combustible fuel?

Combustible fuels are substances that can ignite and produce heat and light when burned. Diesel and gasoline are prime examples of combustible fuels because they are hydrocarbons that release energy upon combustion. This process is essential for powering engines, heating, and generating electricity.

In contrast, water and dirt are not combustible; they do not burn or provide energy through combustion. Compressed air, while it can be involved in combustion processes (such as in internal combustion engines), does not itself act as a fuel because it does not contain combustible material. Therefore, diesel or gasoline distinctly fits the definition of combustible fuel, being designed specifically for combustion applications in various energy systems.