[URL] discusses differences between  reset your computer to a clean Windows 10 version  (If you are using the built in Windows 10 reset, that will roll back to the most recent major version installed on your PC, regardless of the original version installed) Vs reset your computer to the Dell factory image as it was originally shipped, including Dell factory-installed apps and software
When using “Reset this PC,” and reinstalling Windows on a Dell computer, is the installed Windows the most recent Windows version or is it the version that was shipped from the factory?  Or, is there a choice between the factory version or the most recent version? I have asked this question many times and never get the same answer, even from Premium Dell Support. Thanks, Jerry Service Tag 
Reset this PC – Question