What is the best way to prevent rust on the Audi A3's undercarriage?

I recently purchased an Audi A3 and want to keep it in pristine condition. I've noticed some signs of rust on the undercarriage and want to prevent it from spreading. Any tips or recommendations would be greatly appreciated.

The best way to prevent rust on your Audi A3's undercarriage is to regularly wash and wax your car. This will help protect the metal from the elements and corrosive materials on the road. Additionally, regularly inspecting and addressing any scratches or dings on the undercarriage can prevent rust from forming.