What technological advancement is used in modern fuel delivery systems?

The correct option is fuel injection systems, which represents a significant technological advancement in modern fuel delivery systems. Unlike older methods such as carburetors or mechanical fuel pumps that rely on the drag of air to mix fuel and air, fuel injection systems directly deliver fuel into the combustion chamber or intake manifold of the engine. This precision allows for better control over the fuel-air mixture, leading to improved engine efficiency, reduced emissions, and enhanced performance.

Fuel injection systems can optimize performance by adjusting the amount of fuel injected based on various factors such as engine load, temperature, and air intake. This adaptability provides a more efficient combustion process compared to the older technologies, which were less precise and often resulted in wasted fuel and higher emissions.

Overall, fuel injection has become the industry standard in modern automobile engines due to its ability to enhance fuel economy, reduce harmful exhaust emissions, and improve the driving experience.