What is the purpose of the red triangle button in the Audi 80?

I noticed a red triangle button on the dashboard of my Audi 80 and I'm not sure what it does. Can someone explain its purpose?

The red triangle button is actually the emergency button for your hazard lights. In case of an emergency, simply press it to activate all four signal lights and warn others on the road.

That red triangle button is part of the Audi 80's centralized locking system. It allows you to simultaneously lock or unlock all doors with just one press.

The red triangle button is connected to the Audi 80's alarm system. If someone tries to break into your vehicle, it will trigger the alarm and warn you.