Which of the following best describes the role of a fuel filter?

The role of a fuel filter is primarily to clean impurities from the fuel before it enters the engine. This is crucial for maintaining engine performance and longevity, as any dirt, rust, or other contaminants present in the fuel can lead to blockages in the fuel injector and other engine components. By filtering out these impurities, the fuel filter ensures that the engine receives clean fuel, which helps in efficient combustion, optimal engine performance, and reduced wear on internal components.

Other options describe functions that are not the primary role of a fuel filter. For instance, injecting fuel into the engine is the role of the fuel injector, while storing excess fuel relates to fuel tanks rather than filters. Regulating fuel pressure is a function performed by the fuel pressure regulator, not the fuel filter itself. Thus, the correct understanding of the fuel filter's purpose emphasizes its critical role in maintaining fuel cleanliness for a well-functioning engine.