What three components make up a spark ignition system?

A spark ignition system is essential for initiating combustion in gas appliances, particularly in heating systems. The correct composition of this system includes the ignition transformer, a cable, and an electrode.

The ignition transformer is responsible for converting the standard voltage into a much higher voltage necessary to create a spark. This high-voltage spark is what ignites the gas-air mixture in the combustion chamber.

The cable serves as the conduit through which the electrical energy flows from the transformer to the electrode. It must be insulated properly to prevent electrical leakage and ensure that the spark can occur where it is intended.

Finally, the electrode is the actual point where the spark occurs, creating a high-temperature arc that ignites the fuel.

Together, these components work efficiently to ensure reliable ignition in heating systems, making option B the correct answer. The other options may list components that belong to different ignition systems or types of devices, but they do not accurately represent the three components specifically used in a spark ignition system.