Question How do I determine which framework I need to target?

[jcardana]

I'm making a simple file manager for the files created by my Lowrey organ.
I "think" I know that selecting a newest version, in my case 4.8, would require everyone who uses this to install .NET ver 4.8.
but, since this is just using FileStream, StringBuilder, TreeView and Listbox, shall I investigate the origins of those to determine the minimum version to target?

Thanks for your time,
Joe