Brother DCP-4020C - Manual (Page 43)

5 - 3 MAKING COPIES
Using Copy Options key
(Temporary Settings)
When you want to change the settings only for the next copy, use the
Copy Options key.
You can use different combinations. For example, if you want to copy
a photograph on glossy paper with best print quality, press
Copy Options to select BEST in the Quality setting and GLOSSY in
the Paper Type setting.
Copy Options Key