How does the Audi A5 achieve improved fuel efficiency?

I am considering purchasing an Audi A5 and am curious about its fuel efficiency. How does this car manage to achieve improved fuel efficiency compared to other vehicles in its class?

The Audi A5 uses a turbocharged engine with direct injection, allowing for better fuel combustion and therefore improved efficiency.

In addition to its efficient engine, the Audi A5 also utilizes a lightweight and aerodynamic chassis to reduce drag and maximize fuel economy.

The A5 also has a stop-start system that automatically shuts off the engine when the car is idling, saving fuel in situations like traffic or red lights.