How to keep your button selected after clicking away ???

Hey guys

I have a problem with unity's UI system

so I want to keep my buttons selected after clicking away because when you click away it's no longer considered as in highlighted transition mode which means it will be no longer highlighted

so basically I want to archive something like radio buttons but in normal buttons

so for example if I have an options menu where every options has a button I want to keep the selected button selected even if I clicked away so the user will know which setting is actually set and which is not.

I know it would be a bit confusing to understand for some people so I will try my best explaining

lets say I have an options menu where I can change graphics settings so there is low,medium,high and ultra each one has a button so if you clicked on one of the buttons you will change the graphics as intended

but as soon as you click away you no longer know which button is selected because it will go back to the Normal color and not the highlighted color

hopefully you understand what I mean

any idea would be appreciated.

(PS: English is not my native language)