Optiplex 3020 mini (small tower)

I need help guys!

I need to upgrade my graphics card to a 4k I'm not sure is that's even possible!

can you guys help me out on this? 

Intel(R) Core(TM) i5-4570 CPU @ 3.20GHz 3.20 GHz

 ram 8.00 GB

64bit 

windows 10 pro

I Need to know which card i can use to upgrade to 4k

(Mini Tower) Limited space/ 1 Slot

Any help would be appreciated!  

thanks