A fan belt is primarily part of which automotive system?

The fan belt, commonly known as the serpentine belt or drive belt, plays a crucial role in the automotive cooling system. It is responsible for driving the engine's cooling fan, which helps regulate the engine temperature by moving air through the radiator. This airflow is essential to dissipate heat and prevent the engine from overheating.

In this context, the choice regarding the cooling system directly aligns with the function of the fan belt, as it ensures that the cooling fan operates effectively to maintain optimal engine temperatures. This vital interaction underlines the importance of the fan belt in the overall functioning of the vehicle's cooling mechanisms. The other options, such as the fuel system, emission control, and ignition system, relate to different aspects of vehicle operation, but do not involve the direct association with the cooling fan's functionality that the fan belt provides.