Make an Even Background (c4d basics!)

All to often I see this recurring questions on the forums.
"How do I get an even background".
You know, just an object on a white plane that is white in the corners.

Like this but then white please.
Even background

Please do not click on Read More.

Follow up:

Hum You clicked aargh.
Ok in two lines.
1. Add a Compositing Tag to the Floor
2. Check "Compositing Background"
Done. (on request I can produce this tutorial in any color, just write me a letter)
here you go