How does the Audi A5 achieve its fuel efficiency?

I have been considering purchasing an Audi A5. I keep hearing about its amazing fuel efficiency and was wondering how it's able to achieve this compared to other cars in its class. Can anyone shed some light on this?

The Audi A5 has a fuel-efficient 2.0-liter turbocharged engine that delivers power and performance while maintaining efficient fuel consumption. On top of that, Audi's quattro all-wheel drive system distributes power to all four wheels evenly, resulting in improved traction and better fuel efficiency.

The Audi A5 also features a lightweight design, with a body made out of aluminum and high strength steel. This helps to reduce the overall weight of the car, resulting in improved fuel efficiency.

In addition to its efficient engine and lightweight design, the Audi A5 also utilizes a start-stop system that automatically turns off the engine when the car is stopped in traffic, further reducing fuel consumption. The system then quickly restarts the engine when you release the brake.